I believe this is a problem that troubles many iPhone users, the iPhone often loses power quickly. It will be very troublesome if you don’t have a power bank on hand. Don’t worry, learn these five tips, so you don’t have to worry about your iPhone running out of power.
1. Turn Down Your Brightness
Settings → Display & Brightness
This should be the simplest way to save battery life. Because the greater the brightness is, the greater the battery drain you’ll experience.
2. Decrease Auto-Lock Time
Settings → Display & Brightness
When you’re adjusting your brightness, you can also decrease your Auto-Lock time. This setting controls how quickly your display is shut off and your phone is locked after inactivity. Of course, no display on while your phone means less battery drain.
3. Turn Off Wi-Fi and Bluetooth
Settings → Wi-Fi/Bluetooth
This is another simple way to save battery life, since iPhones burn a huge amount of power searching for Wi-Fi and Bluetooth signals. When you are not using them, turn both off, which will extend the battery life a lot.
4. Turn Off Location Services
Settings → Privacy → Location Services
Location services uses GPS, Bluetooth, and Wi-Fi to search your location, buring battery life in the process. If you don’t need this function, turn it off and enjoy more battery.
5. Low Power Mode
Settings → Battery → Low Power Mode
The most straightforward way. Low Power Mode shuts down a whole host of non-essential power-draining features, including automatic downloads and background app refresh. Trust me, it won’t affect your use at all.
Tech leakers 
Sean Lee 
T4TeCH