Black screen crash while playing in a world

When playing, the screen suddenly goes black, stays black for a few seconds before the game crashes and returns me to the home screen. It doesn't seem to be related to anything particular I do in the game, it happens when I'm walking around the world, when I'm mining, when I'm building. If I reload the game after the crash I will have lost 5 or so minutes of progress within the game. It is crashing so often as to make it unplayable! I don't know if it's related but the world doesn't always generate properly either, the screen just goes blue in front of me (like the sky), then when I walk backwards and forwards a few times the world appears bit by bit.

Edited to add: problems persist after update.