Sony Xperia M4 Aqua Problem

[Kenan03]

I have installed the Smart Cooler : https://play.google.com/store/apps/details?id=com.cooler.smartcooler and my phone started to go crazy. When I call someone, he turns off and I have to wait 5-6 minutes to turn on. And repeats. I can use Google Chrome, YT, AliExpress. Can some one tell me how to fix it without losing my data?

EDIT: I uninstalled it, but I'm very scared to try it out again. Please, answer me asap.

[Uliwooly]

@Kenan03

You most likely experience the same issue, report the bugs/issues to the app developer. 

[Kenan03]

But how do I repair my phone without losing data ?

EDIT: I can use my Gmail system app, Music, Album, Camera. But still didn't try to call someone. It's 00:00. :((

[Uliwooly]

@Kenan03

Boot in >>> safe mode > uninstall the app > restart the phone

[Kenan03]

I pressed boot in safemode and now my screen is black. What should i do? Answer me asap.