· Update to the latest software.
o Apple software updates often include advanced energy-saving technologies, so always make sure your device is using the latest version of iOS, macOS, or watchOS.
· Optimize your settings.
o Dim the screen or turn on Auto-Brightness to extend battery life.
o When you use your device to access data, a Wi-Fi connection uses less power than a cellular network.
· Enable low power mode: Introduced with iOS 9, Low Power Mode is an easy way to extend the battery life of your iPhone when it starts to get low.
· View battery usage information.
o Background activity: To improve battery life, you can turn off the feature that allows apps to refresh in the background.
o Location and background location: In Location Services, you can see each app listed with its permission setting. Apps that recently used location services have an indicator next to the on/off switch.
o Home & Lock Screen: In Location Services, you can see each app listed with its permission setting. Apps that recently used location services have an indicator next to the on/off switch.
· No cell coverage and low signal.
o You can optimize your battery life by turning on Airplane mode. Swipe up to open Control Center and tap the Airplane mode icon. Note that you cannot make or receive calls while in Airplane mode.
· Plugin and power on your personal computer to charge your device.
o Make sure your computer is plugged in and powered on when you’re using it to charge your iOS device via USB. If your device is connected to a computer that’s turned off or is in sleep or standby mode, your device’s battery may drain.