Install apk files into Android emulator using adb (android sdk)

1. Install the Android SDK
2. Start the emulator:

   /path/to/android-sdk-macosx/tools/emulator -avd

   and make sure you have tick "Setting -> Applications -> Unknown sources"
3. Install the apk file:

   /path/to/android-sdk-macosx/platform-tools/adb install /path/to/the-app.apk