If your iPhone acted bizarre, stop itself, even when I was 15 or 30% left battery, you need to know that this is not new, and you are not alone. Users have reported this problem on a large scale since the departure of iOS 9. And many people know this same today in 2016.
If your iPhone is shutting down, even when clearly has a reasonable amount of battery, try the following solutions.
1. Reset Hardware
Hard reset usually deals with this problem. Hard reset is the equivalent of "you tried to turn it off and again," but at a much deeper level of the operating system. Usually, it restores the default values.
To perform a hard reset on your iPhone with a physical home button (any iPhone before iPhone 7), hold the "Sleep / Wake" and "Home" buttons for 5 seconds. The iPhone will restart, you will see the flash icon and Apple iPhone come alive.
On the iPhone 7 and iPhone 7 Plus, hold the "Power On / Standby" and "Volume Down" key to do the same.
2. Are you running the latest operating system?
Users reported this problem when iOS 9 was new. The effect was random and no real source of this problem was found.
But users have reported that the operating system upgrade to the latest version usually solves the problem for them. At that time it was iOS 9. At the time of writing it is IOS 10.1.
Therefore, when the phone is started and running (probably after hardware reset), go to "Settings" -> "General" -> "Software Update" and update the latest version of the software .
If the phone does not answer and there is nothing working (including resetting), just place the phone in charing. And I keep there for an hour or not being invasive.
If this does not work, try using another cable, a different AC adapter or trying to charge it from your Mac.
4. Drain at 0%, then fully recharge
If the problem is with the battery indicator (as in the battery statistics are not displayed correctly in the system), the solution is to empty the battery at 0% (in fact the phone until it Stop because there is no charge left), then load everything up to 100%.
5. Restore via iTunes
One of the last stations for this kind of thing, is to restore your phone to the new state via iTunes.
Step 1: Connect your iPhone to your Mac / PC and open iTunes.
Step 2: Once your iPhone is recognized, go to the section and click "Backup Now" to create a local backup of your phone
Step 3: After completing the backup, click "Restore iPhone." This will start the process of downloading the latest iOS software, completely clean your device and install the new operating system on your device.
Once done, your phone will be restored as it was when I got it. When finished, you are asked if you want to restore the backup you made earlier. Once done, all your applications and data to your iPhone.
6. Apple Contact
If you have done all of the above, we are responsible for any software problem that could be responsible for shutting your iPhone out randomly, even when charges have left.
But we can not do everything. Your iPhone may have a damaged battery, or any other component. If your iPhone has old 3-4 years, which is a very real possibility (I've seen it a year, the iPhone 6 also).
The best option is to contact Apple (call 1-800-694-7466) or go to the nearest Apple Store or Apple Service Station. If you are under warranty or have Apple Care (always a good idea), Apple could give you a new device or have to pay for repairs.
How do you solucionaste?
How solucionaste this problem on your device? Share with us in the comments below, it could help other people facing the same problem.