I wondered that. I think it's just on samsung tablets/phones. When you press it , the unit goes into lock, but the apps carry on running. They want it so the app pauses when user locks phone/tablet. This is why I think the Samsung SDK is needed.
Maybe TGC could liase with samsung and try to get some of the commands and requirements into AGK2.
Google Play do a 70/30 split, but Samsungs store gives you 100% for the first 3 months, 90% for the next 3 months and 80% from there after. That's a good deal, which I'm sure the AppGameKit community would like a piece of.

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