Make it easy for a kid to do what s/he wants, and hard to do what s/he doesn't. Anything which disrupts the play is bad, and the worst is transitions to the App

Make it easy for a kid to do what s/he wants, and hard to do what s/he doesn't. Anything which disrupts the play is bad, and the worst is transitions to the App Store (kid has no idea what is going on, just that something wonderful went away for no apparent reason). I'll pay for toddler versions which go all out to avoid anything but core simple fun play. If anything short of pressing Home means the kid has to hand me the tablet to "fix it", I want my money back.