This has happened to me multiple times now over the past few weeks.

When flying with the elytra on a local world (normal survival) the game often randomly freezes for a couple seconds. Sometimes it resumes after the freeze is over but there is a chance the game stays frozen and crashes. It has also managed to make the entire phone crash multiple times resulting in a forced restart of Android. 

My phone used to run the game with stable fps and no crashes. Also this issue only seems to happen on local worlds, not on servers or worlds hosted by friends. Overall the performance is much worse on local worlds for some reason. I already have all possible settings on lowest.

Phone: Samsung Galaxy A51, 4 GB ram, enough free storage