Update README.md

Author: nekocode

README.md

@@ -1 +1,49 @@
-# README
+# README
+
+This project shows how to build an android application with kotlin and some useful libraries. It intergates the [Meepo](https://github.com/nekocode/Meepo) library to create activity & broadcast routers. And use kotlin language sugars to make their usages simpler. For example:
+
+```kotlin
+// Goto a new activity
+activityRouter().gotoXxxActivity(this)
+
+// Broadcast a action
+broadcastRouter().tellSomeSth(this)
+
+// Receiver a broadcast
+registerLocalReceiver({ _, intent ->
+    val action = (intent ?: return@registerLocalReceiver).action
+            ?: return@registerLocalReceiver
+    when (action) {
+        "ACTION_XXX" -> {
+            // Do sth
+        }
+    }
+}, "ACTION_XXX", "ACTION_XXX2")
+```
+
+It intergates the [Retrofit](https://github.com/square/retrofit) library to help making http requests:
+
+```kotlin
+gankIoService().picApi.getMeiziPics(1, 0)
+    // ...
+```
+
+And it splits the backend logic (file and network operations that not relate to ui) into a submodule. And make them easier to test:
+
+```kotlin
+class GankIoServiceTest {
+    private val gankIoService = GankIoService(OkHttpClient(), Gson())
+
+    @Test
+    fun getMeiziPics() {
+        gankIoService.picApi.getMeiziPics(10, 0)
+                .test()
+                .assertNoErrors()
+                .assertValue { response ->
+                    !response.error && response.results.size == 10
+                }
+    }
+}
+```
+
+Please reference the code to see more details.