Closed Why does some of built in apps disappear?

[Black_Saber]

Magandang hapon sa lahat! I wanna ask why did some of my sister's built in apps suddenly disappear.

She was surfing the net, tapos may mga apps na kusang nag-i-install like Super file manager, Tennis etc. It keeps on vibrating. And then biglang nag-restart phone niya. It displays "Android is restarting". Hinintay nalang nyang matapos marestart and continued surfing the net. But later on, napansin niyang nawala yung ibang apps niya, like built-in browser, maps, calculator, and email. It doesn't show up on her launcher or home screen even in the app menu. Na-format na niya phone niya pero hindi parin bumabalik. Anong pwedeng gawin para bumalik ang mga nawala mga boss?

Salamat sa mga sasagot.

 

[K I N J A Z]

mga possible cause(s):

• corrupted firmware
• package installer duplicated with virus (from ads)
• virus

mga possible solution(s):

• re-flash stock firmware
• root your device & install xposed framework. (reinstall lost app, & change it to system app)

 

[Black_Saber]

mga possible cause(s):

• corrupted firmware
• package installer duplicated with virus (from ads)
• virus

mga possible solution(s):

• re-flash stock firmware
• Troot your device & install xposed framework. (reinstall lost app, & tchange it to system app)

Thanks sa pagsagot, boss. Paano po ba i-reflash yung stock firmware?