Accessing and controlling services on Android

I would like to create an androi开发者_JS百科d app/service that will control Android services, in particular the Media Player. This is different from the playing a audio file, in my case the user has already launched the Media Player with their own song/playlist and wish to send skip/stop/... commands.

The AOSP Media Player has no public documented and supported API. Moreover, the app you think of as the "Media Player" does not exist on all devices.