Just to second Dubdub's recommendations: If a hard reset fixes things for a while, you may want to live with it. I wouldn't, but you need to decide.

I would try deleting app world, do a hard reset, and then reinstall app world again, and see what happens.

Worst case is as Dubdub says. Wipe the smartphone with JL_CMDER and the reinstall the OS. Then restore you data and, at first, only the third-party apps you absolutely need. Then, test for 24-48 hours, and after that add one app at a time, followed by 24-48 hours before you add the next.
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