Hi, I have a Nexus 7 2013 tablet, running a rooted android 4.4.2 and I'm testing minecraft pe 0.9.0 build 1. This happened to both creative and survival worlds. They became corrupted after playing for a while.
What caused it:
1. Playing mcpe 0.9.0 build 1
2. Creating one infinite creative world and one survival
3. Playing each of them for a few minutes (20-30).
4. In creative after jumping of the cliff, in survival while randomly walking around, the game crashed.
5. When I try to load those worlds again, the game crashes every time.

Also, it just happened to an old world as well.