I don't know when it started but my phone keeps installing these apps after i uninstall them "Doctor Clean" "Super File Manager" "Super Locker" and there are more,but these are the ones i remember.They all have the same start screen and their notifications look the same,so they're all coming from a single source. I keep uninstalling them and like a day later they install again.I'm afraid that installing an antivirus may slow down my phone. I have downloaded one thing from an unknown source and many things from listentoyoutube.com Maybe this caused the "virus". Any solutions? Antivirus suggestions that don't slow down my phone?