Malware comes back after serveral factory resets!!! What can I do?

[AC Question]

samsung galaxy s3 neo purchesed on amazon through italy (i´m in spain)

SO... i somehow caught some maleware, popup ads when viewing certain apps, after the factory reset i got so paranoid i only put AVG Antivirus and WhatsApp and it came back! it only shows when i go inside AVG and then only when i navigate inside it not in the first screen!

possible suspects that i have were all bundled with the mechine so:
1 - Polaris office viwer5
2 - story album
3 ChatOn
4 SNS provider
5 samsung apps

i read somewhere that sometimes these malware come disguised as system updates, in any case i didn´t approve anything and i think i saw it happaning and couldn´t stop it (as suddenly these programs decided to automatically download and update) when it finished i opened the avg anti virus and sure enough the popups were there

the only strange thing i did today was go to the center of the city where i can imagine someone might have somehow physically phished my phone?
it might also be that since i didn´t change passwords they just found a way to push the same thing back inside?

either way i feel like throwing the thing to the trash (alas i don´t have money to buy another phone!)
obviusly AVG does not recognize any threat! i´m weary of downloading other anti malware programs cuz at this point i don´t trust anything.

what can i do? apart of a factory reboot and a change of passwords?
how will i know that it´s not compromised still if the virus is somehow bundled with the mechine?
should i root it and remove everything samsung put on it?

 

[Gaccount Lcount]

i´ve been reading some more and it seems that polaris office viewer 5 could indeed be the issue!
so what can i do if it comes with the phone it self...?
i´m weary of rooting the phone since i really cant afford to brick it by mistake! i didn´t even buy it it was a birthday present and my first smart phone altogether, i only downloaded apps from google play and only very trusted ones (watsapp, RealRacing 3, skype, AVG antivirus,) when i first got this thing i remember thinking it might have been polaris because i downloaded some book to read and it started some time after the first use of polaris... but i couldn´t be sure...

on a personal note: i´m a pretty paranoid type and i wasn´t too excited to enter the world of smart phones in the first place... but i needed a new cell and it was a present. right now i feel invaded and impotent, i can´t believe that samsung allows this and my mind is reeling with paranoid ideas about how some criminal can listen and track my every move, use my phone for god knows what too...
and i´m also quite disappointed to not have 100% control of my machine (referring to android...)

anyway any kind of ideas or seggestions are more then welcome! a solution or just someone with the same problem would also be awesome!
thanks in advance!

 

[Gaccount Lcount]

i´m having a complicated week so i didn´t have time for doing another factory reboot, it has now spread to chrome navigator too giving me popups on the bottom.
please help!

 

[T Busby]

I'm sorry to hear that you are having an unpleasant time dealing with these issues. The pre-installed applications you suggested earlier may not contain the malware as I have had no issues with them in the past. When and where do the popups appear?
There could be a downloaded application to blame.

To see if this is true, you can reboot the device into safe mode. This will disable downloaded applications temporarily to see if there are problems. To do this, hold down power button until a menu pops up. Press and hold on the power off option and it should ask if you want to hoot into safe mode. Select yes and it should reboot into safe mode. If the problem still persists then it is something to do with the system.

And also if possible could you take screenshots of the popup that is appearing? Most Android phones can do this by pressing and holding the power and home button together for approximately 1 second.