How can I tell if my iPhone has been compromised?

If you feel an unauthorized person/app is remotely using, controlling or monitoring your device, then that is possible only if you have done one or more of the following Don'ts...

1. Don't hand over an iPhone to kids or to a stranger without Enabling Guided Access
2. Don't share Apple IDs
3. Don't Jailbreak
4. Don't share sensitive information pertaining to your device
5. Don't give in to Phishing
6. Don't plug in your device in Airports and Public places through third-party cables and trust the device. Beware of Juice Jacking. (Especially in India)
7. Don't leave your iPhone unlocked and unattended in public places like offices, schools, malls, etc.

If one of the above is true then quickly change the Apple ID Password and Return iPhone settings to their defaults.

go to ur settings, scroll down and press on “privacy” then turn on lockdown mode

Queen_48 wrote:

I haven't done any of the above.

it’s improbable that your device is hacked.

See If you think your Apple Account has been compromised - Apple Support

Safety Check for an iPhone with iOS 16 or later - Apple Support

u can also do a “safety check” and “manage sharing and access” (also in privacy)