Affects 0.13.0-Present. I sometimes have my Windows 10 Computer join my Lg Optimus Exceed 2's world to build things and test multiplayer features. I noticed one day that sometimes my world crashes and I lose data. Once, it happened without the computer joined to the world, so I don't know if it has anything to do with the computer. It seems to just crash at random times, and I then realize that my phone says "Minecraft PE has stopped!" and my computer says "Disconnected from Server" if it is joined.
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I thought that this was a completely different problem. Thanks for letting me know that this was already reported.
Duplicate of MCPE-12347 – If you have not, please use the search function in the future, to see if your bug has already been submitted, as currently over 47% of tickets are being closed as duplicate.