Can't find some apps in play store while others don't work After I factory reset my s4 some apps was reinstalled easily, while others didn't work as it used and some can't be found in play store(youtube downloader). All music downloader won't work. I had simple mp3 downloader before now it doesn't work. I need your help
TubeMate (and all similar YouTube video downloaders) were removed from the Play Store for violating Google's Terms and Conditions. Simple MP3 Downloader was also removed for this reason. You probably downloaded the apps before they were removed from the Play Store, so that is why you had them before.

You can still install those two apps to your phone from manually installing the .apk files for TubeMate and Simple MP3 Downloader.