One of the biggest battery hogs of a smartphone besides the large screen is the multiple radios and receivers inside of them, including the cellular radios, Wi-Fi, Bluetooth and GPS. If you need to conserve battery but don't want to shut your phone down completely, you may want to consider putting your phone into Airplane Mode, which shuts down all those radios but leaves your phone offline but fully functional. In this standby mode, you should lose no more than 1-2% per hour of battery, maybe even less.
Airplane mode originally got its name--not surprisingly--as a result of the requirement to shut off your phone's receivers on an airplane while still keeping access to your "portable electronic device." Of course, nothing prevents you from activating it while you are firmly planted on the ground, too. There are two ways to access airplane mode:
- Press-and-hold the power button for a few seconds until the power menu pop up appears and select Airplane Mode.
- Swipe down from the top-right of the screen to access the Connections dropdown menu and select "Turn on Airplane Mode"
When you are done, a small airplane icon ( ) will appear on the right of the top status bar indicating that Airplane Mode has been turned on. Once in Airplane mode, you can still turn on any individual receiver for your phone to access. So, if you are on a flight that has Wi-Fi, you can enable Airplane Mode and then just turn Wi-Fi back on (either directly in the Wi-Fi app or by once again swiping down from the top-right of the screen to access the Connections dropdown menu and selecting Wi-Fi). Once you are ready to turn Airplane mode off, just perform either of the same steps as above but selecting "Turn off Airplane Mode"