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Very Simple QLab Controller app
Play Store: https://play.google.com/store/apps/details?id=com.jwetzell.qlabcontroller
Play Store (Alpha) https://play.google.com/apps/testing/com.jwetzell.qlabcontroller
Coming to iOS very soon
Google Group: https://groups.google.com/forum/#!forum/qcontroller
Link to a very 'in-the-works' app I have been making to control QLab using Android devices.