Question App to prevent kids from pressing buttons whilst watching videos?

I'm thinking about the time the kids are in the car on a long journey and I give them my android tablet to watch a video.

Is there any way I can lock down all control of the tab (except power button perhaps) and remotely control the tab from my phone such that if they have it in their hands they don't have to worry about pressing the screen/soft buttons?

Or is this the next multi-million dollar app?