both my kids ipads won't open the app after the latest update. after trying to open you get the mojang logo then white screen, then you are back on the menu page of the ipad. 

it's been 5 days now and my kids have created a significant world that they can't access, please help. I've tried closing the world, the app, closing down the ipad. letting it sit for a day off. any suggestions before I have to reinstall and start again, and break my kids hearts!