
Fear not, there are a couple of ways to reboot the Galaxy S6 when it freezes for no apparent reason. The first is a simple one that has been a part of competing phones with non-removable batteries for a long time – you can simply press and hold the power button for 10 seconds to force it to restart (just like you would hold down the power button on a PC to force it to power down.)
If that fails, you can use a simple three-button combination. Press and hold the volume down, home and power/lock buttons until you come to a Warning screen as shown in the image below. Here you can press the volume down key to restart the phone. In case you were wondering, this trick works for the Galaxy S6 edge as well.