My iPhone turns itself off when I’m in the middle of using it. Is this a battery issue?
If you have an iPhone 6s model, you may be experiencing the technical issue that caused Apple to announce a battery-replacement program last month. The battery defect is not as serious as the problems with Samsung’s Galaxy Note 7 phones last year, and a note on Apple’s site states, “This is not a safety issue and only affects devices within a limited serial number range that were manufactured between September and October 2015.”
If you have a different iPhone model (or an iPhone 6s unaffected by the battery problem), the unexpected shutdowns could be caused by a number of things. Make sure your phone is up-to-date with the latest version of the iOS software by opening the Settings app and tapping Software Update — or by connecting the phone to the computer and letting iTunes check for you. Update your apps as well.
The condition of the iPhone’s lithium-ion battery could also be the culprit. Batteries do wear out after a period of regular use and recharging, and the power cell in an older model may need to be replaced. Apple charges $79 for a battery swap, but can also diagnose different power issues (as can other repair shops) if the battery is fine. The weather may also be a factor: Using the iPhone in extremely cold temperatures can temporarily decrease its battery life.