I'd rather keep the two separate if at all possible. It keeps the two fairly isolated from one another, which I think is better. For music at least, the pick activity is pretty similar to part of the music app's main UI, which isn't really the case here. What I really want is to have some sort of "internal activity" to use to open up the share window from the manager.

I'd forgotten entirely a bout postMessage/onmessage, but those would probably make this a little saner.