Updated Jul 14,2016 | by Niko
As iPhone users, you may face an unexpected issue, and maybe wondering why my iPhone keeps restarting intermittently or constantly. However, most of you have no idea about why iPhone keeps restarting over and over again. In the following article, we will help you find out the possible reasons, and also offer you solutions to fix this "my iPhone keeps restarting" issue.
Before making any changes, we suggest you backup your iPhone via iTunes, iCloud or other alternatives tools like IOTransfer. In this way, there is no chance for you to lose your important data, even if something goes terribly wrong.
Make Sure Your iPhone iOS is Up to Date
Sometimes, your iPhone keeps restarting because of the older version of iOS. iOS update, which comes with bug fixes and new features, can possibly help fix "my iPhone keeps restarting" issue. Go to Settings > General > Software Update or connect your iPhone to iTunes and see if any software update is available. Anyway, you need to install it and make sure your iPhone iOS is up to date. In addition to iOS update, Apple Official also suggests you update all your apps as well.

Uninstall Suspicious, Newly Installed Apps
Also, the "my iPhone keeps restarting" issue might be caused by a newly installed app. Although it is quite rare for an app to cause this kind of issue, it has possibility. If the "my iPhone keeps restarting" issue only began to happen after installing a certain app, uninstall it may get the issue fixed properly.
Reset, Force Restart or Restore Your iPhone
Some settings may conflict with some certain programs. Since you cannot make sure what they are exactly, so reset your iPhone setting is a possible solution to fix "my iPhone keeps restarting" issue. Go to Settings > General (at the bottom) > Reset.

To force restart your iPhone, you need to press both the Home button and Power button for 10 seconds at least, until you see the Apple logo appears on the screen.
Restore your iPhone will wipe out all the content, settings and even the OS on your iPhone. Restore your iPhone to factory settings may help the device stop restarting. Once the restore finishes, your iPhone will restart. Now, you can set it up as new or reload the content & information from your backup.
Hardware Failure
Also, "my iPhone keeps restarting" is probably caused by hardware failure, faulty battery in most cases. For old devices, definitely, the battery performance is not as good as it used to be. If your iPhone has been used for many years, and you are facing the constant restarting issue, you may consider battery replacement. While if your iPhone device is new, you may need to check for other hardware problems and repair your iPhone.

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