Sudden battery drain
Phone overheating when not in use
Unusual spikes in data usage
Apps you did not install
Pop-ups or ads appearing unexpectedly
Phone running slowly or crashing often
Settings changing by themselves
Unknown calls, texts, or emails sent from your phone
Friends reporting strange messages from you
Microphone, camera, or location indicators turning on unexpectedly
Login alerts from accounts you did not access
Passwords or account details no longer working
Security apps disabled without your action
Browser redirects to unfamiliar sites
High phone bill or unexpected charges
Device behavior that changes after installing a new app or clicking a link