Suspicious Activity
One of the first signs that your phone has been hacked is suspicious activity, says JP Zhang, founder of SoftwareHow. “If you receive and messages stating that your device, email, or cloud account has been used to sign into a new device and you don’t recognize this, you have probably been hacked,” Zhang says. “Other evidence that indicates a hack has occurred is your contacts receiving messages from your account that you have not sent. Oftentimes, these messages are sent with instructions to click a link that will then infect the recipient’s devices.”
If you have been a victim of a data breach or identity fraud in the past, this also increases the likelihood of another attack on your email or cloud accounts, according to Zhang.
Strange Alerts and Pop-Ups
“Hackers typically mess up with your phone settings,” says Alina Clark, co-founder of Cocodoc. “New intrusive popups or the appearance of content that you haven't subscribed to should send alarm bells ringing in your head.”
A Sudden Increase In Data Usage
“Even though a surge in data increase can be occasioned by increased browsing and increased bandwidth demands, it can also be a sign of hacking,” Clark says. “Hackers usually use your phone's bandwidth to control the phone. This ends up increasing the amount of data used almost exponentially. A sudden surge of data needs, without the attendant increase in internet usage, can be a grim sign for any iPhone user.”
The Appearance Of Calls Or Texts You Didn’t Make
“Text messages are huge conduits for phishing attacks and brute-force breaching,” Clark says. “Any new text messages, especially if they come with weird links, can be a result of hacking. On the other hand, the appearance of calls that you didn't make on your call history should be a sign of something deeper.”
Phone Lags And Crashes
“Slow page loads, frequent hanging and crashing can also be signs of hacking,” Clark says. “The workload from hacking can, in practice, make your phone slower and more susceptible to hanging and crashing.”
Increased Battery Drainage
It’s not your imagination: if you’ve been hacked, your phone’s battery power could be diminishing at a much faster rate. “A sudden decrease in your phone's battery retention can be a sign of the battery having issues, or the phone needing more power due to hacking,” Clark says.
If you suspect you’ve been hacked, experts recommend changing all of your passwords that are associated with hacked accounts. Delete any suspicious apps and run anti-malware software on your phone, Clark says. And once you are up and running again, use two-factor authentication to boost your password security.