How can one tell if the iPhone has been hacked?

Hey there,

Is there anything that makes you think that your iPhone has been hacked?

To make sure that your iPhone does not contain any security gaps, update it to the latest version ☞ Update your iPhone or iPad - Apple Support

Also we recommend you to review and change what you’re sharing and secure your device when someone else may have had physical access.

How to take action

There are more things that you have to check it in your iPhone to be confident that your iPhone is safety ☞ Personal Safety User Guide - Apple Support

1) You gave your phone to someone for a hour or two

2) That someone was also given your Apple ID and Password

3) That someone has amazing knowledge and equipment

If you think your Apple ID has been compromised - Apple Support

For all practical purposes your iPhone can’t be hacked, except by someone with physical possession of it while it is unlocked.