basic readme.

README.md

@@ -1,5 +1,55 @@
 <a href="https://nbd.wtf"><img align="right" height="196" src="https://user-images.githubusercontent.com/1653275/194609043-0add674b-dd40-41ed-986c-ab4a2e053092.png" /></a>
 
-The Open Bitcoin Wallet is a fork of [Simple Bitcoin Wallet](https://github.com/btcontract/wallet) focused on providing a good experience.
+# The _Open Bitcoin Wallet_
+
+The _Open Bitcoin Wallet_ is an Android Bitcoin and Lightning wallet, a fork of [_Simple Bitcoin Wallet_](https://github.com/btcontract/wallet) focused on providing a pleasant and simple experience with advanced features.
+
+Some of the features it includes are:
+
+  - Lightweight Bitcoin wallet that uses Electrum servers
+    - can use an Electrum server specified by the user or random ones
+    - support for RBF and CPFP
+    - coin control (select which UTXOs to spend or not)
+    - payments to multiple addresses
+  - Standalone, autonomous Lightning capabilities:
+    - can connect to any node
+    - open channels, close channels, force-close channels, close channels to specific address
+    - route payments without the use of any third-party service, all routing done on the wallet
+    - offer to retry payments with increased fee tolerance if the first attempts fail
+  - Hosted Channels
+    - lightweight credit-based virtual channels that use an open and interoperable protocol
+    - can open hosted channels to any node that supports the host side of the protocol and can be connected to
+  - Full TOR support
+    - built-in TOR, no Orbot needed
+  - Split-payments support
+    - the same invoice from A can be paid by multiple wallets (B, C, D and so on) atomically
+    - perfect for splitting bills at restaurants
+  - LNURL support
+    - lnurl-channel, lnurl-hosted-channel
+    - lnurl-pay, lightning address, comments, message, URL and AES-encrypted `successAction`s
+    - lnurl-withdraw
+    - keyauth (lnurl-auth)
 
 ![obiwan](https://user-images.githubusercontent.com/1653275/186679611-c5c25d94-752a-4368-a0e4-7e7109fa5548.gif)
+
+## IMMORTAN
+
+_Open Bitcoin Wallet_ is based on [IMMORTAN](https://github.com/nbd-wtf/immortan), a versatile, flexible and reasonable library for building lightweight Bitcoin and Lightning wallets.
+
+## How to build from source
+
+Run this:
+
+```
+git clone https://github.com/nbd-wtf/obw.git
+cd obw
+./gradlew assembleDebug
+```
+
+The APK will be at `app/build/outputs/apk/debug`.
+
+Other commands: `./gradlew installDebug`, `./gradlew assembleRelease`, `./gradlew bundleRelease` (with Gradle options `-PSTORE_FILE=... -PSTORE_PASSWORD=... -PKEY_PASSWORD=... -PKEY_ALIAS=...` when signing to publish to Google Play Store).
+
+## License
+
+Apache.