I would love it if the sermon that is paying would show up on the lock screen with the play/pause buttons. That way you wouldn't have to unlock the device and go back into the app.
The most recent updates to iOS and Android added this feature.
I believe this would work if they get the player to be recognized/integrated with the phone OS. I submitted a request, and it is currently under review: http://accentral.userecho.com/topics/83-integrate-the-ac-central-player-into-the-system-player/
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