Device dies, then game is lost or has converted modes upon relaunch

What I expected to happen was...:
I guess I expected that the game would be saved and preserved intact if my device were to die due to low power...

What actually happened was...:
When my device died, my game was lost (I was like six gold ingots away from building the better reactor, btw). The first time this happened was months ago... like in June of 2013. This happened again a few months later, and I stopped playing because I got so frustrated ... as if my efforts were forever to be fruitless. Then, a couple months ago, I started playing again (it's just a damn fine game, I must admit). A couple days ago, my device crashed again (yes, I'm terrible at plugging the thing in when I should, I know), and I just opened it to take a look at the world I have been working on all winter only to find that it got weird again. My world lost its name and has now become creative mode (it had been survival before my device died).

Steps to Reproduce
1. Use a kindle fire HD
2. Play MCPE survival mode until the device runs out of power
3. Charge device
4. Launch MC
5. If world still exists, do it again while services plugged in.