Unknown Apps Installed

Hello guys,recently i'm getting unknown apps installed on my iphone..Not just any apps.they are apps like the game mortal kombat,Avira antivirus,Damn daniel,etc...I had this before so i new formatted my iphone,erased everything.after i logged in the same apple id ofc..again with strange apps.I don't know if my apple id was hacked cause i don't think this is possible.I used it only on my phone,it's not even jailbroken.Please someone reply to me as soon as possible can my iphone be hacked?And if yes,in which way it is,adware or malware accesing ur pics calls camera.i logged in the same apple id on 2 phones but apps like that weren't on them..why on my phone?