This is a tip to keep in your favorites, as everyone will one day need it.
Although it usually works well, sometimes the iPhone (iPad or iPod touch) crashes completely and you don’t know what to do. Whether while running an application or when connecting an accessory not compatible with the device. There is no computer system in which this never happens.
What not everyone knows is that the device has a form of startup (hard reset) that makes it possible to restore the system in the event of a crash. If your device does not turn on, does not turn off, or is stuck on the same screen, follow the recommendations below.
To reset the device (in the Windows world, a Control-Alt-Del), just hold the buttons Rest and Start for about 10 or 20 seconds, until the Apple appears on the screen. After that, just release and wait for the device to restart.
From there, it should work normally, if it is not a more serious problem.
Remember that the trick does not apply to devices with a fully discharged battery. In this case, it is necessary to leave at least 20 minutes connected to the electrical current for it to give a sign of life.
For devices starting with iPhone 7, the procedure has changed slightly. Check out this other article.