3. Low Power Mode
As you probably already know by now, you can turn on Low Power Mode at any time. You don’t have to wait for the battery power to drop below 20% in order for the iOS to automatically turn the Low Power Mode on. You should keep it on all the time. It reduces or turns off the apps that run in the background and thus it reduces the overall load on the system and the battery. This is a good way to extend the overall longevity of your iPhone.