Add usage to readme

ExampleApp/README.md

@@ -19,4 +19,27 @@ Peripheral mode gives you the overview on how to advertise specific service with
 2. In `Signing & Capabilities` set team for iOS distribution to your "personal team".
 3. Run the project on "My Mac" target
 4. Without stopping the project, run again on iOS device.
-5. Enjoy BLE connection between your device and your mac 🎉
+5. Enjoy BLE connection between your device and your mac 🎉
+
+## Usage
+
+Typical steps to see the BLE connection:
+
+1. On iOS device, choose `Peripheral` mode, then `Update`
+2. Enter service UUID (f.e. "AAA1") and Characteristic UUID (f.e. "BBB2"), then tap `Advertise`
+3. On Mac, choose `Central`, then `Specific`
+4. Enter the same service and characteristic UUIDs as in `2.`
+5. Click `Connect`. If the connection is successfull, you should see `Read value` label turning green
+6. On iOS device enter some text in the `Value` field. Tap `Update`
+7. Observe updated value on your Mac 🎉
+
+Alternatively, you can try advertising in different modes, f.e. write:
+1. On iOS device, choose `Peripheral` mode, then `Write`
+2. Enter service UUID (f.e. "AAA1") and Characteristic UUID (f.e. "BBB2"), then tap `Advertise`
+3. On Mac, choose `Central`, then `List`. Then click the magnifying glass toolbar icon in the upper-right-hand corner to start scanning for peripherals
+4. On the list, find a peripheral named `RxBluetoothKit`. Tap it
+5. On the list of peripheral's services, find a service with uuid entered in `2.`
+6. On the list of the chosen service's characteristics, find the one you entered in `2.`
+7. Click `Write`
+8. Enter string value to be written to a characteristic. Click `Write`
+9. Observe the written value on your iOS device 🎉