Most Android device manufacturers have added some form of power-saving mode. You can automatically hobble your phone's features or shut down specific apps when your battery dwindles below a predetermined level.
Stock Android only offers battery stats for now, but Android Lollipop has a battery saver option built in (which means most phones running Android 5 will too in the future). If you can't find a power saving option, check out an app like Juice Defender.
2. Automate your phone
You don't need your phone syncing away through the night, so why not introduce a bedtime routine that automatically silences it and kills your data and Wi-Fi connections? With apps like AutomateIt and Tasker you can also automatically turn things on and off based on triggers and rules you define.
3. Uninstall or disable apps
Delve into Settings > Apps and flick over to the 'All' tab to find a complete list of your apps. Anything there that you don't use is a candidate for the uninstall pile. In their infinite wisdom, carriers and manufacturers sometimes block you from uninstalling their apps, but you usually have the option to disable them instead and it's worth doing.
4. Hibernate or freeze apps
You may also consider installing Greenify to get a good look at what is running and automatically hibernate apps that you aren't using, so they aren't eating system resources unless you start them up.
You'll need to root your device to really take full advantage, which is simple enough but will take a little time to manage if you're new to the process. If you do decide to root then you may also consider Titanium Backup Pro for freezing unwanted apps.
5. Streamline your home screen
The busier your home screen, the more battery life it's going to suck. Get rid of widgets that you don't need, and consider reducing refresh rates. Animation costs power, so ditch the live wallpapers.
If you have a phone with an AMOLED display (such as nearly all of the high end Samsungs or the new Moto X), then use a dark background for the home screen and a dark theme in general. The technology achieves deep blacks by not lighting up those pixels and so dark backgrounds can save you some power.
6. Tweak display settings
Your screen brightness is going to have a big impact on your battery. Don't rely on auto-brightness because it will generally be set higher than you really need. Reduce brightness manually and keep it as low as is comfortable. You can always pull down the notification shade and tweak it quickly via the quick settings when you have to.
You should also reduce the screen time out in display settings under sleep. The faster your Android device fades to black when not in use, the more power you'll save.
7. Turn off vibrations
Some vibrations aren't good; when it comes to your Android phone or tablet they can be an unnecessary battery killer.
Start with haptic feedback for key presses. You'll usually find the option to turn 'Vibrate on keypress' off in Settings > Language & input in the options for the keyboard you are using. You could also turn off 'Sound on keypress' for extra saving.
You can also go into Settings > Sound and turn off 'Vibrate when ringing'. You'll find a Vibrate option that you can turn off in your SMS app settings as well.
8. Turn off notifications
Do you need to know every time someone likes a post or comments on something you've engaged with on Facebook? Do you want to hear about the latest special offer or new app in your notification shade?
When you install any app, it automatically gains the right to fire notifications at you, but you can stop it in Settings > Apps by tapping on the app and clearing the 'Show notifications' box.
9. Reduce or stop auto-syncing
Do you need to check for emails every five minutes? Reduce the frequency of your syncing and use push settings for email wherever possible.
For non-essential apps and services you could just stop background syncing altogether and tell them to only refresh when you actually start the app up. This is usually done through the settings in the app itself.
10. Location services
Go to Settings > Location and you can see which services and apps are trying to track you. Switch the mode to lower accuracy or just turn it off and you can save a lot of power.
11. Get a spare battery, portable charger or case
It's an obvious suggestion, but a spare battery, a portable charger or an extended battery case are sure-fire methods of extending your battery life.
Most are quite discreet now as well, meaning it's not a hulking great brick you need to carry around, but one that could possibly fit in your wallet. Of course, if you go for a bigger model they often offer quick charging capabilities or oodles of power so will offer more than a couple of charges.
12. Underclocking the CPU
If you're willing to root then you can sweep away bloatware and get an optimized custom ROM, you can even download an app like SetCPU for Root Users and tell your processor to run at a slower speed in order to use less power. It's an extreme step, but it definitely has an impact.