saving the battery on a phone

If you find your phone burns a lot of battery. There are a few things you can do.

Put your phone on airplane mode when you're not expecting a call or not actively doing anything that requires the internet.

Turn off data and wifi when you're not using them.

Close all apps and reboot the device. Sometimes even when an app isn't open it can become truent and soak up cpu, memory and bandwidth. You'll also notice things will speed up too.

Delete any apps you don't use much. Some apps have a tendency of doing things without your permission which will burn up power without you realizing it a lot of the time.

Turn down the brightness of the screen when you don't need it like if you're somewhere dark.

Keep in mind how Power hungry the app is. Things that require the internet burn a lot. So do a lot of games. So don't do that when you're trying to save your battery.

Use power save if you're not doing much that is taxing to your device.

Take photos and videos at a lower resolution.