doc: add android configuration section

docs/android/README.md

@@ -1,3 +1,52 @@
 # Building Android App
 
-Building android app is very easy. Just download [Android Studio](http://developer.android.com/sdk/index.html) and import project from [app-android](../../app-android/).
+### Requirements
+* [Android Studio](http://developer.android.com/sdk/index.html)
+
+### Development
+To change source code of android app import project from [app-android](../../app-android/) in Android Studio.
+
+### Configuration
+Configuration is performed in [actor-bootstrap/app-android/src/main/java/im/actor/enterprise/MessengerApplication.java](../../app-android/src/main/java/im/actor/enterprise/MessengerApplication.java)
+
+All customizations are inside `onConfigureActorSDK` method, and performed via methods of `ActorSDK.sharedActor()`
+
+```
+@Override
+public void onConfigureActorSDK() { 
+	//customizations goes here
+	//ActorSDK.sharedActor().set...
+}
+```
+
+List of avaiable customizations:
+#### Set server endpoints
+In case of self hosted solution, the most important parameter is server endpoints. You can set them like this: 
+
+```
+ActorSDK.sharedActor().setEndpoints(new String[] {
+		"tcp://93.184.216.34:9070"
+});
+```
+Endpoint is:
+```
+<schema>://<server address>:<port>
+```
+where:
+ - schema: tcp or tls in case of secured connection
+ - server address: your server ip/dns
+ - port: your endpoint port
+
+#### Change application name
+If you want to change application name, you can do it this way:
+```
+ActorSDK.sharedActor().setCustomApplicationName("My awesome messenger");
+ActorSDK.sharedActor().setAppName("My awesome messenger");
+```
+
+#### Receive push notification without configuring Google push service
+Android application can work as background task, receiving push notification, it can replace Google pushes, or coexist with them.
+You can enable background service this way:
+```
+ActorSDK.sharedActor().setIsKeepAliveEnabled(true);
+```