App has crashed

Hi, guys.
I’ve got one problem that i can’t solve.
Some apps crash sometimes with no reason.
Month ago i tried to change davlik to art by changing that txt file, i don’t remember the name. After that my apps started crashing a lot. For example Google Play or vk(social network). I tried to hard reset, upgrade to 4.2.8i or to 4.5i. Nothing has helped. I don’t know what to do. Is there any way to clear my phone properly (all system files should be reseted).
Thx :)

Contributor

Read the QUstion and Answer guide, figure out what problem you have and described it in detail please. (Including the phone you are talking about!)

Close this one, I’ll create new)

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