Constant crashes, ALL THE TIME

My Minecraft PE is constantly crashing. This might be a personal thing, but it happens all the time. The screen goes black and I get kicked out of the app. Sometimes it even does it multiple times in a row so I can't even re-open it. If someone can help, that would be very much appreciated.

UPDATE: I thought it might've been because I didn't have enough memory, but I've got more than a gigabyte of free space. I can't use the game anymore as it crashes whenever I open a world. Help.