diff --git a/Sources/KlaviyoSwift/KlaviyoAPI.swift b/Sources/KlaviyoSwift/KlaviyoAPI.swift
index e61bb31c..347701e1 100644
--- a/Sources/KlaviyoSwift/KlaviyoAPI.swift
+++ b/Sources/KlaviyoSwift/KlaviyoAPI.swift
@@ -39,12 +39,12 @@ struct KlaviyoAPI {
     static var requestRateLimited: (KlaviyoRequest) -> Void = { _ in }
     static var requestHttpError: (KlaviyoRequest, Int, Double) -> Void = { _, _, _ in }
 
-    var send: (KlaviyoRequest) async -> Result<Data, KlaviyoAPIError> = { request in
+    var send: (KlaviyoRequest, Int) async -> Result<Data, KlaviyoAPIError> = { request, attemptNumber in
         let start = Date()
 
         var urlRequest: URLRequest
         do {
-            urlRequest = try request.urlRequest()
+            urlRequest = try request.urlRequest(attemptNumber)
         } catch {
             requestFailed(request, error, 0.0)
             return .failure(.internalRequestError(error))
@@ -86,7 +86,7 @@ struct KlaviyoAPI {
 }
 
 extension KlaviyoAPI.KlaviyoRequest {
-    func urlRequest() throws -> URLRequest {
+    func urlRequest(_ attemptNumber: Int = StateManagementConstants.initialAttempt) throws -> URLRequest {
         guard let url = url else {
             throw KlaviyoAPI.KlaviyoAPIError.internalError("Invalid url string. API URL: \(environment.analytics.apiURL)")
         }
@@ -97,6 +97,7 @@ extension KlaviyoAPI.KlaviyoRequest {
         }
         request.httpBody = body
         request.httpMethod = "POST"
+        request.setValue("\(attemptNumber)/50", forHTTPHeaderField: "X-Klaviyo-Attempt-Count")
 
         return request
     }
diff --git a/Sources/KlaviyoSwift/KlaviyoState.swift b/Sources/KlaviyoSwift/KlaviyoState.swift
index 8eba10ee..6f9a72d4 100644
--- a/Sources/KlaviyoSwift/KlaviyoState.swift
+++ b/Sources/KlaviyoSwift/KlaviyoState.swift
@@ -98,7 +98,7 @@ struct KlaviyoState: Equatable, Codable {
     var initalizationState = InitializationState.uninitialized
     var flushing = false
     var flushInterval = StateManagementConstants.wifiFlushInterval
-    var retryInfo = RetryInfo.retry(0)
+    var retryInfo = RetryInfo.retry(StateManagementConstants.initialAttempt)
     var pendingRequests: [PendingRequest] = []
     var pendingProfile: [Profile.ProfileKey: AnyEncodable]?
 
diff --git a/Sources/KlaviyoSwift/NetworkSession.swift b/Sources/KlaviyoSwift/NetworkSession.swift
index 0afe5a7f..d39868d4 100644
--- a/Sources/KlaviyoSwift/NetworkSession.swift
+++ b/Sources/KlaviyoSwift/NetworkSession.swift
@@ -14,7 +14,8 @@ func createEmphemeralSession(protocolClasses: [AnyClass] = URLProtocolOverrides.
         "User-Agent": NetworkSession.defaultUserAgent,
         "revision": NetworkSession.currentApiRevision,
         "content-type": NetworkSession.applicationJson,
-        "accept": NetworkSession.applicationJson
+        "accept": NetworkSession.applicationJson,
+        "X-Klaviyo-Mobile": NetworkSession.mobileHeader
     ]
     configuration.protocolClasses = protocolClasses
     return URLSession(configuration: configuration)
@@ -24,6 +25,7 @@ struct NetworkSession {
     fileprivate static let currentApiRevision = "2023-07-15"
     fileprivate static let applicationJson = "application/json"
     fileprivate static let acceptedEncodings = ["br", "gzip", "deflate"]
+    fileprivate static let mobileHeader = "1"
 
     static let defaultUserAgent = { () -> String in
         let appContext = environment.analytics.appContextInfo()
diff --git a/Sources/KlaviyoSwift/SDKRequestIterator.swift b/Sources/KlaviyoSwift/SDKRequestIterator.swift
index 555c667a..78c0f7fe 100644
--- a/Sources/KlaviyoSwift/SDKRequestIterator.swift
+++ b/Sources/KlaviyoSwift/SDKRequestIterator.swift
@@ -137,6 +137,7 @@ public func requestIterator() -> AsyncStream<SDKRequest> {
             KlaviyoAPI.requestFailed = { _, _, _ in }
             KlaviyoAPI.requestCompleted = { _, _, _ in }
             KlaviyoAPI.requestHttpError = { _, _, _ in }
+            KlaviyoAPI.requestRateLimited = { _ in }
         }
         KlaviyoAPI.requestStarted = { request in
             continuation.yield(SDKRequest.fromAPIRequest(request: request, response: .inProgress))
@@ -151,5 +152,8 @@ public func requestIterator() -> AsyncStream<SDKRequest> {
         KlaviyoAPI.requestHttpError = { request, statusCode, duration in
             continuation.yield(SDKRequest.fromAPIRequest(request: request, response: .httpError(statusCode, duration)))
         }
+        KlaviyoAPI.requestRateLimited = { request in
+            continuation.yield(SDKRequest.fromAPIRequest(request: request, response: .reqeustError("Rate Limited", 0.0)))
+        }
     }
 }
diff --git a/Sources/KlaviyoSwift/StateManagement.swift b/Sources/KlaviyoSwift/StateManagement.swift
index a4e94ee0..d41b8260 100644
--- a/Sources/KlaviyoSwift/StateManagement.swift
+++ b/Sources/KlaviyoSwift/StateManagement.swift
@@ -21,6 +21,7 @@ enum StateManagementConstants {
     static let cellularFlushInterval = 30.0
     static let wifiFlushInterval = 10.0
     static let maxQueueSize = 200
+    static let initialAttempt = 1
 }
 
 enum RetryInfo: Equatable {
@@ -293,7 +294,7 @@ struct KlaviyoReducer: ReducerProtocol {
             state.requestsInFlight.removeAll { inflightRequest in
                 completedRequest.uuid == inflightRequest.uuid
             }
-            state.retryInfo = RetryInfo.retry(0)
+            state.retryInfo = RetryInfo.retry(StateManagementConstants.initialAttempt)
             if state.requestsInFlight.isEmpty {
                 state.flushing = false
                 return .none
@@ -313,8 +314,13 @@ struct KlaviyoReducer: ReducerProtocol {
                 return .none
             }
             let retryInfo = state.retryInfo
-            return .run { send in
-                let result = await environment.analytics.klaviyoAPI.send(request)
+            var numAttempts = 1
+            if case let .retry(attempts) = retryInfo {
+                numAttempts = attempts
+            }
+
+            return .run { [numAttempts] send in
+                let result = await environment.analytics.klaviyoAPI.send(request, numAttempts)
                 switch result {
                 case .success:
                     // TODO: may want to inspect response further.
@@ -361,7 +367,7 @@ struct KlaviyoReducer: ReducerProtocol {
             switch retryInfo {
             case let .retry(count):
                 exceededRetries = count > ErrorHandlingConstants.maxRetries
-                state.retryInfo = .retry(exceededRetries ? 0 : count)
+                state.retryInfo = .retry(exceededRetries ? 1 : count)
             case let .retryWithBackoff(requestCount, totalCount, backOff):
                 exceededRetries = requestCount > ErrorHandlingConstants.maxRetries
                 state.retryInfo = .retryWithBackoff(requestCount: exceededRetries ? 0 : requestCount, totalRetryCount: totalCount, currentBackoff: backOff)
diff --git a/Tests/KlaviyoSwiftTests/APIRequestErrorHandlingTests.swift b/Tests/KlaviyoSwiftTests/APIRequestErrorHandlingTests.swift
index 445abc85..e29f9fff 100644
--- a/Tests/KlaviyoSwiftTests/APIRequestErrorHandlingTests.swift
+++ b/Tests/KlaviyoSwiftTests/APIRequestErrorHandlingTests.swift
@@ -11,21 +11,22 @@ import XCTest
 
 let TIMEOUT_NANOSECONDS: UInt64 = 10_000_000_000 // 10 seconds
 
-@MainActor
 class APIRequestErrorHandlingTests: XCTestCase {
+    @MainActor
     override func setUp() async throws {
         environment = KlaviyoEnvironment.test()
     }
 
     // MARK: - http error
 
+    @MainActor
     func testSendRequestHttpFailureDequesRequest() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         let request = initialState.buildProfileRequest(apiKey: initialState.apiKey!, anonymousId: initialState.anonymousId!)
         initialState.requestsInFlight = [request]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.httpError(500, TEST_RETURN_DATA)) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.httpError(500, TEST_RETURN_DATA)) }
 
         _ = await store.send(.sendRequest)
 
@@ -35,13 +36,14 @@ class APIRequestErrorHandlingTests: XCTestCase {
         }
     }
 
+    @MainActor
     func testSendRequestHttpFailureForPhoneNumberResetsStateAndDequesRequest() async throws {
         var initialState = INITIALIZED_TEST_STATE_INVALID_PHONE()
         let request = initialState.buildProfileRequest(apiKey: initialState.apiKey!, anonymousId: initialState.anonymousId!)
         initialState.requestsInFlight = [request]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.httpError(400, TEST_FAILURE_JSON_INVALID_PHONE_NUMBER.data(using: .utf8)!)) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.httpError(400, TEST_FAILURE_JSON_INVALID_PHONE_NUMBER.data(using: .utf8)!)) }
 
         _ = await store.send(.sendRequest)
 
@@ -53,17 +55,18 @@ class APIRequestErrorHandlingTests: XCTestCase {
             $0.flushing = false
             $0.queue = []
             $0.requestsInFlight = []
-            $0.retryInfo = .retry(0)
+            $0.retryInfo = .retry(1)
         }
     }
 
+    @MainActor
     func testSendRequestHttpFailureForEmailResetsStateAndDequesRequest() async throws {
         var initialState = INITIALIZED_TEST_STATE_INVALID_EMAIL()
         let request = initialState.buildProfileRequest(apiKey: initialState.apiKey!, anonymousId: initialState.anonymousId!)
         initialState.requestsInFlight = [request]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.httpError(400, TEST_FAILURE_JSON_INVALID_EMAIL.data(using: .utf8)!)) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.httpError(400, TEST_FAILURE_JSON_INVALID_EMAIL.data(using: .utf8)!)) }
 
         _ = await store.send(.sendRequest)
 
@@ -75,12 +78,13 @@ class APIRequestErrorHandlingTests: XCTestCase {
             $0.flushing = false
             $0.queue = []
             $0.requestsInFlight = []
-            $0.retryInfo = .retry(0)
+            $0.retryInfo = .retry(1)
         }
     }
 
     // MARK: - network error
 
+    @MainActor
     func testSendRequestFailureIncrementsRetryCount() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         let request = initialState.buildProfileRequest(apiKey: initialState.apiKey!, anonymousId: initialState.anonymousId!)
@@ -88,18 +92,19 @@ class APIRequestErrorHandlingTests: XCTestCase {
         initialState.requestsInFlight = [request, request2]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.networkError(NSError(domain: "foo", code: NSURLErrorCancelled))) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.networkError(NSError(domain: "foo", code: NSURLErrorCancelled))) }
 
         _ = await store.send(.sendRequest)
 
-        await store.receive(.requestFailed(request, .retry(1)), timeout: TIMEOUT_NANOSECONDS) {
+        await store.receive(.requestFailed(request, .retry(2)), timeout: TIMEOUT_NANOSECONDS) {
             $0.flushing = false
             $0.queue = [request, request2]
             $0.requestsInFlight = []
-            $0.retryInfo = .retry(1)
+            $0.retryInfo = .retry(2)
         }
     }
 
+    @MainActor
     func testSendRequestFailureWithBackoff() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         initialState.retryInfo = .retryWithBackoff(requestCount: 1, totalRetryCount: 1, currentBackoff: 1)
@@ -108,7 +113,7 @@ class APIRequestErrorHandlingTests: XCTestCase {
         initialState.requestsInFlight = [request, request2]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.networkError(NSError(domain: "foo", code: NSURLErrorCancelled))) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.networkError(NSError(domain: "foo", code: NSURLErrorCancelled))) }
 
         _ = await store.send(.sendRequest)
 
@@ -120,6 +125,7 @@ class APIRequestErrorHandlingTests: XCTestCase {
         }
     }
 
+    @MainActor
     func testSendRequestMaxRetries() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         initialState.retryInfo = .retry(ErrorHandlingConstants.maxRetries)
@@ -130,7 +136,7 @@ class APIRequestErrorHandlingTests: XCTestCase {
         initialState.requestsInFlight = [request, request2]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.networkError(NSError(domain: "foo", code: NSURLErrorCancelled))) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.networkError(NSError(domain: "foo", code: NSURLErrorCancelled))) }
 
         _ = await store.send(.sendRequest)
 
@@ -138,12 +144,13 @@ class APIRequestErrorHandlingTests: XCTestCase {
             $0.flushing = false
             $0.queue = [request2]
             $0.requestsInFlight = []
-            $0.retryInfo = .retry(0)
+            $0.retryInfo = .retry(1)
         }
     }
 
     // MARK: - internal error
 
+    @MainActor
     func testSendRequestInternalError() async throws {
         // NOTE: should really happen but putting this in for possible future cases and test coverage
         var initialState = INITIALIZED_TEST_STATE()
@@ -152,7 +159,7 @@ class APIRequestErrorHandlingTests: XCTestCase {
         initialState.requestsInFlight = [request]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.internalError("internal error!")) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.internalError("internal error!")) }
 
         _ = await store.send(.sendRequest)
 
@@ -160,12 +167,13 @@ class APIRequestErrorHandlingTests: XCTestCase {
             $0.flushing = false
             $0.queue = []
             $0.requestsInFlight = []
-            $0.retryInfo = .retry(0)
+            $0.retryInfo = .retry(1)
         }
     }
 
     // MARK: - internal request error
 
+    @MainActor
     func testSendRequestInternalRequestError() async throws {
         var initialState = INITIALIZED_TEST_STATE()
 
@@ -173,7 +181,7 @@ class APIRequestErrorHandlingTests: XCTestCase {
         initialState.requestsInFlight = [request]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.internalRequestError(KlaviyoAPI.KlaviyoAPIError.internalError("foo"))) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.internalRequestError(KlaviyoAPI.KlaviyoAPIError.internalError("foo"))) }
 
         _ = await store.send(.sendRequest)
 
@@ -181,12 +189,13 @@ class APIRequestErrorHandlingTests: XCTestCase {
             $0.flushing = false
             $0.queue = []
             $0.requestsInFlight = []
-            $0.retryInfo = .retry(0)
+            $0.retryInfo = .retry(1)
         }
     }
 
     // MARK: - unknown error
 
+    @MainActor
     func testSendRequestUnknownError() async throws {
         var initialState = INITIALIZED_TEST_STATE()
 
@@ -194,7 +203,7 @@ class APIRequestErrorHandlingTests: XCTestCase {
         initialState.requestsInFlight = [request]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.unknownError(KlaviyoAPI.KlaviyoAPIError.internalError("foo"))) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.unknownError(KlaviyoAPI.KlaviyoAPIError.internalError("foo"))) }
 
         _ = await store.send(.sendRequest)
 
@@ -202,19 +211,20 @@ class APIRequestErrorHandlingTests: XCTestCase {
             $0.flushing = false
             $0.queue = []
             $0.requestsInFlight = []
-            $0.retryInfo = .retry(0)
+            $0.retryInfo = .retry(1)
         }
     }
 
     // MARK: - data decoding error
 
+    @MainActor
     func testSendRequestDataDecodingError() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         let request = initialState.buildProfileRequest(apiKey: initialState.apiKey!, anonymousId: initialState.anonymousId!)
         initialState.requestsInFlight = [request]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.dataEncodingError(request)) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.dataEncodingError(request)) }
 
         _ = await store.send(.sendRequest)
 
@@ -222,19 +232,20 @@ class APIRequestErrorHandlingTests: XCTestCase {
             $0.flushing = false
             $0.queue = []
             $0.requestsInFlight = []
-            $0.retryInfo = .retry(0)
+            $0.retryInfo = .retry(1)
         }
     }
 
     // MARK: - invalid data
 
+    @MainActor
     func testSendRequestInvalidData() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         let request = initialState.buildProfileRequest(apiKey: initialState.apiKey!, anonymousId: initialState.anonymousId!)
         initialState.requestsInFlight = [request]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.invalidData) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.invalidData) }
 
         _ = await store.send(.sendRequest)
 
@@ -242,30 +253,32 @@ class APIRequestErrorHandlingTests: XCTestCase {
             $0.flushing = false
             $0.queue = []
             $0.requestsInFlight = []
-            $0.retryInfo = .retry(0)
+            $0.retryInfo = .retry(1)
         }
     }
 
     // MARK: - rate limit error
 
+    @MainActor
     func testRateLimitErrorWithExistingRetry() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         let request = initialState.buildProfileRequest(apiKey: initialState.apiKey!, anonymousId: initialState.anonymousId!)
         initialState.requestsInFlight = [request]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.rateLimitError(nil)) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.rateLimitError(nil)) }
 
         _ = await store.send(.sendRequest)
 
-        await store.receive(.requestFailed(request, .retryWithBackoff(requestCount: 1, totalRetryCount: 1, currentBackoff: 0)), timeout: TIMEOUT_NANOSECONDS) {
+        await store.receive(.requestFailed(request, .retryWithBackoff(requestCount: 2, totalRetryCount: 2, currentBackoff: 0)), timeout: TIMEOUT_NANOSECONDS) {
             $0.flushing = false
             $0.queue = [request]
             $0.requestsInFlight = []
-            $0.retryInfo = .retryWithBackoff(requestCount: 1, totalRetryCount: 1, currentBackoff: 0)
+            $0.retryInfo = .retryWithBackoff(requestCount: 2, totalRetryCount: 2, currentBackoff: 0)
         }
     }
 
+    @MainActor
     func testRateLimitErrorWithExistingBackoffRetry() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         initialState.retryInfo = .retryWithBackoff(requestCount: 2, totalRetryCount: 2, currentBackoff: 4)
@@ -273,7 +286,7 @@ class APIRequestErrorHandlingTests: XCTestCase {
         initialState.requestsInFlight = [request]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.rateLimitError(nil)) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.rateLimitError(nil)) }
 
         _ = await store.send(.sendRequest)
 
@@ -292,7 +305,7 @@ class APIRequestErrorHandlingTests: XCTestCase {
         initialState.requestsInFlight = [request]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.rateLimitError(20)) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.rateLimitError(20)) }
 
         _ = await store.send(.sendRequest)
 
@@ -306,6 +319,7 @@ class APIRequestErrorHandlingTests: XCTestCase {
 
     // MARK: - Missing or invalid response
 
+    @MainActor
     func testMissingOrInvalidResponse() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         initialState.retryInfo = .retryWithBackoff(requestCount: 2, totalRetryCount: 2, currentBackoff: 4)
@@ -313,7 +327,7 @@ class APIRequestErrorHandlingTests: XCTestCase {
         initialState.requestsInFlight = [request]
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
 
-        environment.analytics.klaviyoAPI.send = { _ in .failure(.missingOrInvalidResponse(nil)) }
+        environment.analytics.klaviyoAPI.send = { _, _ in .failure(.missingOrInvalidResponse(nil)) }
 
         _ = await store.send(.sendRequest)
 
@@ -321,7 +335,7 @@ class APIRequestErrorHandlingTests: XCTestCase {
             $0.flushing = false
             $0.queue = []
             $0.requestsInFlight = []
-            $0.retryInfo = .retry(0)
+            $0.retryInfo = .retry(1)
         }
     }
 }
diff --git a/Tests/KlaviyoSwiftTests/AppLifeCycleEventsTests.swift b/Tests/KlaviyoSwiftTests/AppLifeCycleEventsTests.swift
index 4443181b..64e53866 100644
--- a/Tests/KlaviyoSwiftTests/AppLifeCycleEventsTests.swift
+++ b/Tests/KlaviyoSwiftTests/AppLifeCycleEventsTests.swift
@@ -10,7 +10,6 @@ import Combine
 import Foundation
 import XCTest
 
-@MainActor
 class AppLifeCycleEventsTests: XCTestCase {
     let passThroughSubject = PassthroughSubject<Notification, Never>()
 
@@ -25,12 +24,14 @@ class AppLifeCycleEventsTests: XCTestCase {
         }
     }
 
+    @MainActor
     override func setUp() {
         environment = KlaviyoEnvironment.test()
     }
 
     // MARK: - App Terminate
 
+    @MainActor
     func testAppTerminateStopsReachability() {
         environment.notificationCenterPublisher = getFilteredNotificaitonPublished(name: UIApplication.willTerminateNotification)
         let expection = XCTestExpectation(description: "Stop reachability is called.")
diff --git a/Tests/KlaviyoSwiftTests/KlaviyoAPITests.swift b/Tests/KlaviyoSwiftTests/KlaviyoAPITests.swift
index 449d76fc..c05a58b8 100644
--- a/Tests/KlaviyoSwiftTests/KlaviyoAPITests.swift
+++ b/Tests/KlaviyoSwiftTests/KlaviyoAPITests.swift
@@ -17,10 +17,6 @@ final class KlaviyoAPITests: XCTestCase {
         environment = KlaviyoEnvironment.test()
     }
 
-    override func tearDownWithError() throws {
-        // Put teardown code here. This method is called after the invocation of each test method in the class.
-    }
-
     func testInvalidURL() async throws {
         environment.analytics.apiURL = ""
 
@@ -105,7 +101,6 @@ final class KlaviyoAPITests: XCTestCase {
         }) }
         let request = KlaviyoAPI.KlaviyoRequest(apiKey: "foo", endpoint: .createEvent(.init(data: .init(event: .test))))
         await sendAndAssert(with: request) { result in
-
             switch result {
             case let .success(data):
                 assertSnapshot(matching: data, as: .dump)
@@ -134,7 +129,7 @@ final class KlaviyoAPITests: XCTestCase {
 
     func sendAndAssert(with request: KlaviyoAPI.KlaviyoRequest,
                        assertion: (Result<Data, KlaviyoAPI.KlaviyoAPIError>) -> Void) async {
-        let result = await KlaviyoAPI().send(request)
+        let result = await KlaviyoAPI().send(request, 0)
         assertion(result)
     }
 }
diff --git a/Tests/KlaviyoSwiftTests/KlaviyoStateTests.swift b/Tests/KlaviyoSwiftTests/KlaviyoStateTests.swift
index 8677f494..a59445c8 100644
--- a/Tests/KlaviyoSwiftTests/KlaviyoStateTests.swift
+++ b/Tests/KlaviyoSwiftTests/KlaviyoStateTests.swift
@@ -11,7 +11,6 @@ import Foundation
 import SnapshotTesting
 import XCTest
 
-@MainActor
 final class KlaviyoStateTests: XCTestCase {
     let TEST_EVENT = [
         "event": "$opened_push",
diff --git a/Tests/KlaviyoSwiftTests/KlaviyoTestUtils.swift b/Tests/KlaviyoSwiftTests/KlaviyoTestUtils.swift
index abecb16d..251cecb4 100644
--- a/Tests/KlaviyoSwiftTests/KlaviyoTestUtils.swift
+++ b/Tests/KlaviyoSwiftTests/KlaviyoTestUtils.swift
@@ -156,7 +156,7 @@ extension FileClient {
 }
 
 extension KlaviyoAPI {
-    static let test = { KlaviyoAPI(send: { _ in .success(TEST_RETURN_DATA) }) }
+    static let test = { KlaviyoAPI(send: { _, _ in .success(TEST_RETURN_DATA) }) }
 }
 
 extension LoggerClient {
diff --git a/Tests/KlaviyoSwiftTests/StateChangePublisherTests.swift b/Tests/KlaviyoSwiftTests/StateChangePublisherTests.swift
index 94b01934..4cfe4dec 100644
--- a/Tests/KlaviyoSwiftTests/StateChangePublisherTests.swift
+++ b/Tests/KlaviyoSwiftTests/StateChangePublisherTests.swift
@@ -11,12 +11,13 @@ import Foundation
 import XCTest
 @_spi(KlaviyoPrivate) @testable import KlaviyoSwift
 
-@MainActor
 final class StateChangePublisherTests: XCTestCase {
+    @MainActor
     override func setUpWithError() throws {
         environment = KlaviyoEnvironment.test()
     }
 
+    @MainActor
     func testStateChangePublisher() throws {
         let savedCalledExpectation = XCTestExpectation(description: "Save called on initialization")
         // Third call set email should trigger again
@@ -76,6 +77,7 @@ final class StateChangePublisherTests: XCTestCase {
         XCTAssertEqual(count, 2)
     }
 
+    @MainActor
     func testStateChangeDuplicateAreRemoved() throws {
         let savedCalledExpectation = XCTestExpectation(description: "Save called on initialization")
         savedCalledExpectation.assertForOverFulfill = true
diff --git a/Tests/KlaviyoSwiftTests/StateManagementEdgeCaseTests.swift b/Tests/KlaviyoSwiftTests/StateManagementEdgeCaseTests.swift
index 35c53af4..09449939 100644
--- a/Tests/KlaviyoSwiftTests/StateManagementEdgeCaseTests.swift
+++ b/Tests/KlaviyoSwiftTests/StateManagementEdgeCaseTests.swift
@@ -9,14 +9,15 @@
 import Foundation
 import XCTest
 
-@MainActor
 class StateManagementEdgeCaseTests: XCTestCase {
+    @MainActor
     override func setUp() async throws {
         environment = KlaviyoEnvironment.test()
     }
 
     // MARK: - initialization
 
+    @MainActor
     func testInitializeWhileInitializing() async throws {
         let initialState = KlaviyoState(queue: [], requestsInFlight: [])
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
@@ -39,6 +40,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
         _ = await store.send(.initialize(apiKey))
     }
 
+    @MainActor
     func testInitializeAfterInitialized() async throws {
         let initialState = INITIALIZED_TEST_STATE()
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
@@ -57,6 +59,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
 
     // MARK: - Send Request
 
+    @MainActor
     func testSendRequestBeforeInitialization() async throws {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -71,6 +74,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
 
     // MARK: - Complete Initialization
 
+    @MainActor
     func testCompleteInitializationWhileAlreadyInitialized() async throws {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -87,6 +91,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
         _ = await store.send(.completeInitialization(initialState))
     }
 
+    @MainActor
     func testCompleteInitializationWithExistingIdentifiers() async throws {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -110,6 +115,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
 
     // MARK: - Set Email
 
+    @MainActor
     func testSetEmailUninitialized() async throws {
         let expection = XCTestExpectation(description: "fatal error expected")
         environment.emitDeveloperWarning = { _ in
@@ -130,6 +136,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
         await fulfillment(of: [expection])
     }
 
+    @MainActor
     func testSetEmailMissingAnonymousIdStillSetsEmail() async throws {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -153,6 +160,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
 
     // MARK: - Set External Id
 
+    @MainActor
     func testSetExternalIdUninitialized() async throws {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -166,6 +174,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
         _ = await store.send(.setExternalId("external-blob-id"))
     }
 
+    @MainActor
     func testSetExternalIdMissingAnonymousIdStillSetsExternalId() async throws {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -189,6 +198,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
 
     // MARK: - Set Phone number
 
+    @MainActor
     func testSetPhoneNumberUninitialized() async throws {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -202,6 +212,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
         _ = await store.send(.setPhoneNumber("1-800-Blobs4u"))
     }
 
+    @MainActor
     func testSetPhoneNumberMissingApiKeyStillSetsPhoneNumber() async throws {
         let initialState = KlaviyoState(anonymousId: environment.analytics.uuid().uuidString,
                                         queue: [],
@@ -224,6 +235,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
 
     // MARK: - Set Push Token
 
+    @MainActor
     func testSetPushTokenUninitialized() async throws {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -237,6 +249,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
         _ = await store.send(.setPushToken("blob_token", .authorized))
     }
 
+    @MainActor
     func testSetPushTokenWithMissingAnonymousId() async throws {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -254,6 +267,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
 
     // MARK: - Stop
 
+    @MainActor
     func testStopUninitialized() async {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -267,6 +281,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
         _ = await store.send(.stop)
     }
 
+    @MainActor
     func testStopInitializing() async {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -282,6 +297,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
 
     // MARK: - Start
 
+    @MainActor
     func testStartUninitialized() async {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -297,6 +313,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
 
     // MARK: - Network Status Changed
 
+    @MainActor
     func testNetworkStatusChangedUninitialized() async {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -312,6 +329,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
 
     // MARK: - Missing api key for token request
 
+    @MainActor
     func testTokenRequestMissingApiKey() async {
         let initialState = KlaviyoState(
             anonymousId: environment.analytics.uuid().uuidString,
@@ -329,6 +347,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
 
     // MARK: - set enqueue event uninitialized
 
+    @MainActor
     func testEnqueueEventUninitialized() async throws {
         let expection = XCTestExpectation(description: "fatal error expected")
         environment.emitDeveloperWarning = { _ in
@@ -343,6 +362,7 @@ class StateManagementEdgeCaseTests: XCTestCase {
 
     // MARK: - set profile uninitialized
 
+    @MainActor
     func testSetProfileUnitialized() async throws {
         let expection = XCTestExpectation(description: "fatal error expected")
         environment.emitDeveloperWarning = { _ in
diff --git a/Tests/KlaviyoSwiftTests/StateManagementTests.swift b/Tests/KlaviyoSwiftTests/StateManagementTests.swift
index aa90c734..dcdadb74 100644
--- a/Tests/KlaviyoSwiftTests/StateManagementTests.swift
+++ b/Tests/KlaviyoSwiftTests/StateManagementTests.swift
@@ -11,14 +11,15 @@ import Combine
 import Foundation
 import XCTest
 
-@MainActor
 class StateManagementTests: XCTestCase {
+    @MainActor
     override func setUp() async throws {
         environment = KlaviyoEnvironment.test()
     }
 
     // MARK: - Initialization
 
+    @MainActor
     func testInitialize() async throws {
         let initialState = KlaviyoState(queue: [], requestsInFlight: [])
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
@@ -41,6 +42,7 @@ class StateManagementTests: XCTestCase {
         await store.receive(.flushQueue)
     }
 
+    @MainActor
     func testInitializeSubscribesToAppropriatePublishers() async throws {
         let lifecycleExpectation = XCTestExpectation(description: "lifecycle is subscribed")
         let stateChangeIsSubscribed = XCTestExpectation(description: "state change is subscribed")
@@ -73,6 +75,7 @@ class StateManagementTests: XCTestCase {
 
     // MARK: - Set Email
 
+    @MainActor
     func testSetEmail() async throws {
         let initialState = INITIALIZED_TEST_STATE()
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
@@ -87,6 +90,7 @@ class StateManagementTests: XCTestCase {
 
     // MARK: Set Phone Number
 
+    @MainActor
     func testSetPhoneNumber() async throws {
         let initialState = INITIALIZED_TEST_STATE()
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
@@ -101,6 +105,7 @@ class StateManagementTests: XCTestCase {
 
     // MARK: - Set External Id.
 
+    @MainActor
     func testSetExternalId() async throws {
         let initialState = INITIALIZED_TEST_STATE()
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
@@ -115,6 +120,7 @@ class StateManagementTests: XCTestCase {
 
     // MARK: - Set Push Token
 
+    @MainActor
     func testSetPushToken() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         initialState.pushTokenData = nil
@@ -141,6 +147,7 @@ class StateManagementTests: XCTestCase {
         }
     }
 
+    @MainActor
     func testSetPushTokenMultipleTimes() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         initialState.pushTokenData = nil
@@ -171,6 +178,7 @@ class StateManagementTests: XCTestCase {
 
     // MARK: - flush
 
+    @MainActor
     func testFlushUninitializedQueueDoesNotFlush() async throws {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -182,6 +190,7 @@ class StateManagementTests: XCTestCase {
         _ = await store.send(.flushQueue)
     }
 
+    @MainActor
     func testQueueThatIsFlushingDoesNotFlush() async throws {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -193,6 +202,7 @@ class StateManagementTests: XCTestCase {
         _ = await store.send(.flushQueue)
     }
 
+    @MainActor
     func testEmptyQueueDoesNotFlush() async throws {
         let apiKey = "fake-key"
         let initialState = KlaviyoState(apiKey: apiKey,
@@ -204,6 +214,7 @@ class StateManagementTests: XCTestCase {
         _ = await store.send(.flushQueue)
     }
 
+    @MainActor
     func testFlushQueueWithMultipleRequests() async throws {
         var count = 0
         // request uuids need to be unique :)
@@ -246,6 +257,7 @@ class StateManagementTests: XCTestCase {
         }
     }
 
+    @MainActor
     func testFlushQueueDuringExponentialBackoff() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         initialState.retryInfo = .retryWithBackoff(requestCount: 23, totalRetryCount: 23, currentBackoff: 200)
@@ -260,6 +272,7 @@ class StateManagementTests: XCTestCase {
         }
     }
 
+    @MainActor
     func testFlushQueueExponentialBackoffGoesToSize() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         initialState.retryInfo = .retryWithBackoff(requestCount: 23, totalRetryCount: 23, currentBackoff: Int(initialState.flushInterval) - 2)
@@ -280,12 +293,13 @@ class StateManagementTests: XCTestCase {
         // didn't fake uuid since we are not testing this.
         await store.receive(.deQueueCompletedResults(request)) {
             $0.flushing = false
-            $0.retryInfo = .retry(0)
+            $0.retryInfo = .retry(1)
             $0.requestsInFlight = []
             $0.queue = []
         }
     }
 
+    @MainActor
     func testSendRequestWhenNotFlushing() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         initialState.flushing = false
@@ -296,6 +310,7 @@ class StateManagementTests: XCTestCase {
 
     // MARK: - send request
 
+    @MainActor
     func testSendRequestWithNoRequestsInFlight() async throws {
         let initialState = INITIALIZED_TEST_STATE()
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
@@ -307,6 +322,7 @@ class StateManagementTests: XCTestCase {
 
     // MARK: - Network Connectivity Changed
 
+    @MainActor
     func testNetworkConnectivityChanges() async throws {
         let initialState = INITIALIZED_TEST_STATE()
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
@@ -330,6 +346,7 @@ class StateManagementTests: XCTestCase {
 
     // MARK: - Stop
 
+    @MainActor
     func testStopWithRequestsInFlight() async throws {
         // This test is a little convoluted but essentially want to make when we stop
         // that we save our state.
@@ -350,6 +367,7 @@ class StateManagementTests: XCTestCase {
 
     // MARK: - Test pending profile
 
+    @MainActor
     func testFlushWithPendingProfile() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         initialState.flushing = false
@@ -426,6 +444,7 @@ class StateManagementTests: XCTestCase {
 
     // MARK: - Test set profile
 
+    @MainActor
     func testSetProfileWithExistingProperties() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         initialState.phoneNumber = "555BLOB"
@@ -441,6 +460,7 @@ class StateManagementTests: XCTestCase {
 
     // MARK: - Test enqueue event
 
+    @MainActor
     func testEnqueueEvent() async throws {
         var initialState = INITIALIZED_TEST_STATE()
         initialState.phoneNumber = "555BLOB"
@@ -452,6 +472,7 @@ class StateManagementTests: XCTestCase {
         }
     }
 
+    @MainActor
     func testEnqueueEventWhenInitilizingSendsEvent() async throws {
         let initialState = INITILIZING_TEST_STATE()
         let store = TestStore(initialState: initialState, reducer: KlaviyoReducer())
diff --git a/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoAPITests/testSuccessfulResponseWithEvent.1.txt b/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoAPITests/testSuccessfulResponseWithEvent.1.txt
index e983bc39..fafe69a5 100644
--- a/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoAPITests/testSuccessfulResponseWithEvent.1.txt
+++ b/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoAPITests/testSuccessfulResponseWithEvent.1.txt
@@ -9,7 +9,10 @@
   ▿ httpMethod: Optional<String>
     - some: "POST"
   ▿ allHTTPHeaderFields: Optional<Dictionary<String, String>>
-    - some: 0 key/value pairs
+    ▿ some: 1 key/value pair
+      ▿ (2 elements)
+        - key: "X-Klaviyo-Attempt-Count"
+        - value: "0/50"
   ▿ httpBody: Optional<Data>
     - some: 0 bytes
   - httpBodyStream: Optional<NSInputStream>.none
diff --git a/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoAPITests/testSuccessfulResponseWithProfile.1.txt b/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoAPITests/testSuccessfulResponseWithProfile.1.txt
index 60cd6017..9563cd57 100644
--- a/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoAPITests/testSuccessfulResponseWithProfile.1.txt
+++ b/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoAPITests/testSuccessfulResponseWithProfile.1.txt
@@ -9,7 +9,10 @@
   ▿ httpMethod: Optional<String>
     - some: "POST"
   ▿ allHTTPHeaderFields: Optional<Dictionary<String, String>>
-    - some: 0 key/value pairs
+    ▿ some: 1 key/value pair
+      ▿ (2 elements)
+        - key: "X-Klaviyo-Attempt-Count"
+        - value: "0/50"
   ▿ httpBody: Optional<Data>
     - some: 0 bytes
   - httpBodyStream: Optional<NSInputStream>.none
diff --git a/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoAPITests/testSuccessfulResponseWithStoreToken.1.txt b/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoAPITests/testSuccessfulResponseWithStoreToken.1.txt
index 98f1c938..b80d173f 100644
--- a/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoAPITests/testSuccessfulResponseWithStoreToken.1.txt
+++ b/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoAPITests/testSuccessfulResponseWithStoreToken.1.txt
@@ -9,7 +9,10 @@
   ▿ httpMethod: Optional<String>
     - some: "POST"
   ▿ allHTTPHeaderFields: Optional<Dictionary<String, String>>
-    - some: 0 key/value pairs
+    ▿ some: 1 key/value pair
+      ▿ (2 elements)
+        - key: "X-Klaviyo-Attempt-Count"
+        - value: "0/50"
   ▿ httpBody: Optional<Data>
     - some: 0 bytes
   - httpBodyStream: Optional<NSInputStream>.none
diff --git a/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testLoadNewKlaviyoState.1.txt b/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testLoadNewKlaviyoState.1.txt
index 4cabef0e..7be1f88b 100644
--- a/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testLoadNewKlaviyoState.1.txt
+++ b/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testLoadNewKlaviyoState.1.txt
@@ -15,4 +15,4 @@
   - queue: 0 elements
   - requestsInFlight: 0 elements
   ▿ retryInfo: RetryInfo
-    - retry: 0
+    - retry: 1
diff --git a/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testStateFileExistsInvalidData.1.txt b/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testStateFileExistsInvalidData.1.txt
index 4cabef0e..7be1f88b 100644
--- a/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testStateFileExistsInvalidData.1.txt
+++ b/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testStateFileExistsInvalidData.1.txt
@@ -15,4 +15,4 @@
   - queue: 0 elements
   - requestsInFlight: 0 elements
   ▿ retryInfo: RetryInfo
-    - retry: 0
+    - retry: 1
diff --git a/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testStateFileExistsInvalidJSON.1.txt b/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testStateFileExistsInvalidJSON.1.txt
index 4cabef0e..7be1f88b 100644
--- a/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testStateFileExistsInvalidJSON.1.txt
+++ b/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testStateFileExistsInvalidJSON.1.txt
@@ -15,4 +15,4 @@
   - queue: 0 elements
   - requestsInFlight: 0 elements
   ▿ retryInfo: RetryInfo
-    - retry: 0
+    - retry: 1
diff --git a/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testValidStateFileExists.1.txt b/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testValidStateFileExists.1.txt
index 4cabef0e..7be1f88b 100644
--- a/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testValidStateFileExists.1.txt
+++ b/Tests/KlaviyoSwiftTests/__Snapshots__/KlaviyoStateTests/testValidStateFileExists.1.txt
@@ -15,4 +15,4 @@
   - queue: 0 elements
   - requestsInFlight: 0 elements
   ▿ retryInfo: RetryInfo
-    - retry: 0
+    - retry: 1
diff --git a/Tests/KlaviyoSwiftTests/__Snapshots__/NetworkSessionTests/testCreateEmphemeralSesionHeaders.1.txt b/Tests/KlaviyoSwiftTests/__Snapshots__/NetworkSessionTests/testCreateEmphemeralSesionHeaders.1.txt
index 0cce6297..82436a64 100644
--- a/Tests/KlaviyoSwiftTests/__Snapshots__/NetworkSessionTests/testCreateEmphemeralSesionHeaders.1.txt
+++ b/Tests/KlaviyoSwiftTests/__Snapshots__/NetworkSessionTests/testCreateEmphemeralSesionHeaders.1.txt
@@ -1,5 +1,5 @@
 ▿ Optional<Dictionary<AnyHashable, Any>>
-  ▿ some: 5 key/value pairs
+  ▿ some: 6 key/value pairs
     ▿ (2 elements)
       - key: "Accept-Encoding"
       ▿ value: 3 elements
@@ -9,6 +9,9 @@
     ▿ (2 elements)
       - key: "User-Agent"
       - value: "FooApp/1.2.3 (com.klaviyo.fooapp; build:1; iOS 1.1.1) klaviyo-ios/3.0.4"
+    ▿ (2 elements)
+      - key: "X-Klaviyo-Mobile"
+      - value: "1"
     ▿ (2 elements)
       - key: "accept"
       - value: "application/json"