The component that uses the most energy on your smartphone is the screen. The more you use it, the faster your battery drains. Using the auto dimming feature helps use less battery. You can also shorten the delay time to turn screen off when you are finished using it for a while.
Watching a streaming video movie requires your phone’s screen to be on continuously, to maintain an active Internet connection, and the phone’s processor and graphics processor also use juice to decode the video and audio.
Streaming music also uses more battery than music stored on the phone, due to network activity of streaming.
Using maps for long trips and your phone’s screen is on, and the app forces the phone’s GPS circuitry to refresh at a more frequent rate than in normal usage. It is also making heavier use of cellular and WI-Fi connections in order to aid in pinpointing your location.
Pop up ads use much processor and waste battery use as much as twice as what it would if you used an ad blocker.
Push messages also use up the battery faster. Why not set the email to only check once every thirty minutes, or each hour, or never, and check mail when you want to, not when someone decides to interrupt you. Same with contacts updates and calendar changes. You can always switch back if you do not notice a noticeable increase in battery life.
Keep your phone relatively warm. Cold weather (below about 60) is a major battery drainer for any battery, not just phone batteries.
If you do not need it, turn GPS and WiFi off until you need them. The constant pinging wastes a battery charge. If you are in a store or another place you do not wish to be disturbed, skip the vibrate mode and just turn on Airplane Mode. All your messages, mail, etc., will arrive when you turn Airplane Mode off.
If you have a battery saving mode on your phone, use it. You will not lose features, it will just keep the automatic pinging and background apps to a minimum.
You can check your settings to see which apps are gobbling most of your resources and turn them off or delete them if you do not need them. You can also turn off GPS or WiFi access for those apps that really do not need these features.
Last, if you are in an area of bad reception, your phone works overtime to find a signal. Use Airplane Mode until you move closer to populated areas. Incidentally, if you notice your battery draining faster than normal and your usage or apps have not changed, might be time to buy a new battery.