How to block keystroke malware?

[Android Central Question]

My Samsung note 5 has been loaded with a keystroke detector by a hacker through a video. Ideally would love to remove and block it too, but barring that, are there any apps that will block it from picking up any more info? They already knew my email password, and that's been changed via another computer, but don't want to sign back into my email on this phone with the new password until I know the problem no longer exists. Appreciate any advice. Not a techie by any means, so be kind :0

 

[Rukbat]

About the only way is reflashing the ROM and reinstalling all your apps from Play. (You don't know what other apps have been infected.) See [Samsung] How to flash Stock ROM via ODIN.