If all of that isn’t enough, you can get a little bit more from your charge by enabling Airplane Mode. Ostensibly designed for, you guessed it, airplanes, this shuts off the radios for things like cellular data, WiFi, and Bluetooth. Charging with that stuff disabled will save you a few minutes than it’d take otherwise, depending on how long you’re plugged in.
The trade-off is that you’re disconnecting yourself from the outside world. There’ll be no calls, no texts, no notifications. That kind of defeats the purpose of a smartphone in the first place. Still, if you absolutely need to get as much life as you can, it’s something.
Apple implemented a less stringent version of this idea called Low Power Mode into iOS 9. It works similarly, just to a lesser extent. It can help in a pinch, but it makes your smart device dumber.