Your Apple iPhone can contain quite a bit of your personal data, depending on how you use it. Email addresses, phone numbers, passwords, banking information, travel plans, and anything else you regularly enter into your iPhone is all subject to theft in the event that your device is hacked. Checking your iPhone for proper operation and signs of intrusion are critical safety steps when protecting your data and keeping your private information secure.
Double-Check Your Bill
The most obvious sign that your iPhone has been hacked is the appearance of strange entries on your phone bill. If you're seeing purchases from the iTunes Store that you didn't make or inexplicably high data usage, it's entirely possible your device has been compromised. Sit down and analyze your bill each month to make sure all of the charges are in line with your normal usage patterns. Contact your cellular provider if you see any unusual billing activity.
Check Your Texts
Malicious software has been discovered that spreads from iPhone to iPhone via text message. Unfortunately for users, the simple reception of such a message is all it takes to compromise the device. If you have strange, unexplained messages on your iPhone composed of odd characters or a single square, your device might already be infected with malicious software. Bring it in for immediate service, if you believe this to be the case.
Malicious software will demand resources from your iPhone and make it harder for you to do the things you normally do. If your phone suddenly becomes sluggish, starts dropping calls, or frequently becomes unresponsive for no apparent reason, the cause could be a malicious application drawing resources away from the phone's normal tasks. Unusually high battery usage is also a sign of a potential hack.
If your iPhone is often warm, even when not in use, it could be a sign that someone other than you is using the phone and piggy-backing on your cellular service. A warm iPhone could also be an iPhone left in the car or performing a background software update, but continued heat generation from a device that should be idling might be a hint of a compromised device.