Some functions on your phone use a lot of power and therefore significantly reduce the battery life. You can reduce the power consumption by turning on low power mode.
Step 1 of 4
Press Settings.
Step 2 of 4
Press Battery.
Step 3 of 4
Press the indicator next to "Low Power Mode" to turn on the function.
Step 4 of 4
Slide your finger upwards starting from the bottom of the screen to return to the home screen.