I’ve had some reports of the upgrade process damaging people’s worlds.
If you have a valuable world:
- Please back it up frequently to Dropbox or SD card, and especially before opening it for the first time in a new version of the game
- Make sure that you have plenty of free space on device before upgrading your worlds
I’ve done all I could to make the upgrade process work smoothly. It worked fine for thousands of worlds, including hundreds that I have tested it on personally. But once in a while some unforeseen combination of bad luck may throw it off.
Even Challenger blew up, even though NASA said the chance of failure was 1:100000.
Be safe. Back up your valuable worlds.