Unfortunately, you're never going to get a week's use out of a smartphone, and that's for some very good reasons. Put simply, even the best batteries don't have enough reserves to power big, bright screens along with Wi-Fi, Bluetooth, GPS and 3G.
However, by following our advice and making a few changes to your phone's settings (and maybe even changing the way you use your phone a little) you should be able to extend its battery life by a good chunk.
These days there's a huge choice of portable USB battery packs, which you can use to give your smartphone's battery a recharge on the go. Plus, if you have a popular handset, you may find there are specific cases which incorporate batteries to give you extra power at the expense of only a little more bulk and weight.What we're not going to suggest here is to use your phone less. Our aim here is to show you how to reduce your handset's power consumption without making it unusable.
So, here are 10 ways you can boost your smartphone's battery life
You love your smartphone's large, colourful display, but it's the battery's mortal enemy. More than any other component of your phone, the display consumes battery life at a devastating pace. Most phones include an auto-brightness feature that automatically adjusts the screen's brightness to suit ambient lighting levels.
This mode uses less power than constantly running your screen at full brightness would, of course, but you'll get even better results by turning your screen's brightness down to the lowest setting that you can tolerate and leaving it there. Even if you do nothing else we suggest, following this one tip will extend the life of your battery dramatically.
2. Keep the screen timeout short
Under your phone's display settings menu, you should find an option labeled 'Screen Timeout' or something similar. (On an iPhone, look for Auto-Lock in the General settings menu.) This setting controls how long your phone's screen stays lit after receiving input, such as a tap.
Every second counts here, so set your timeout to the shortest available time. On most Android phones, the minimum is 15 seconds. If your screen timeout is currently set to 2 minutes, consider reducing that figure to 30 seconds or less. On an iPhone, the minimum you can set is 1 minute.
No matter now much you love using Bluetooth with your hands-free headset, your wireless speaker or activity tracker, the extra radio is constantly listening for signals from the outside world. When you aren't in your car, or when you aren't playing music wirelessly, turn off the Bluetooth radio. This way, you can add an hour or more to your phone's battery life.
4. Turn off Wi-Fi
As with Bluetooth, your phone's Wi-Fi radio is a serious battery drainer. While you will need to use your home or office Wi-Fi connection rather than 3G for internet access and other data services, there's little point in leaving the Wi-Fi radio on when you're out and about. Toggle it off when you go out the door, and turn it back on only when you plan to use data services within range of your Wi-Fi network. Android users can add the Wi-Fi toggle widget to their home screen to make this a one-tap process.
In iOS 6, it's easier than ever to toggle Bluetooth and Wi-Fi on and off. Tap Settings, and you'll see the options right at the top.
5. Go easy on the GPS
Another big battery sucker is your phone's GPS, which is a radio that receives signals from the global network of satellites to triangulate your phone's location on the Earth's surface. Various apps access your phone's GPS to provide services ranging from finding nearby restaurants to checking you in on social networks.And, of course, for satellite navigation.
As a user, you can revoke some apps' access to your phone's GPS. When you install them, many apps will ask you for permission to use your location. When in doubt, say no. (And if a game, screensaver, or wallpaper app asks for your location, you should be suspicious about why it wants that data in the first place.)
Multitasking - the ability to run more than one app at a time - is a powerful smartphone feature. It also burns a lot of energy, because every app you run uses a share of your phone's processor cycles. By killing apps that you aren't actually using, you can drastically reduce your CPU's workload and cut down on its power consumption.
For Android phones, which are notorious battery hogs due to their wide-open multitasking capabilities, we like an app called Advanced Task Killer, which has an auto-kill feature that polices your apps throughout the day. However, from Ice Cream Sandwich onwards, you can tap the recent apps multitasking button and simply swipe apps off the screen to close them. In some cases this doesn't completely stop the app, so tap Settings, Apps then go to Running, and hit the Stop button.
In iOS, double-tap the Home button until the multitasking tray appears, hold an icon until an X appears, and tap the X to close the app. It's worth closing all the apps and rebooting your phone from time to time as well. If you're a fan of Words With Friends, make sure you close this after you play as it's a well-known iPhone battery killer.
7. Don't use vibrate
Prefer to have your phone alert you to incoming calls by vibrating rather than playing a ringtone? We understand the inclination; unfortunately, vibrating uses much more power than playing a ringtone does. After all, a ringtone only has to make a tiny membrane in your phone's speaker vibrate enough to produce sound.
In contrast, the vibration motor rotates a small weight to make your whole phone shake. That process takes a lot more power. If you don't want to be disturbed audibly, consider turning off all notifications and leave the phone in view so you can see when a new call is coming in. This approach is as courteous to your battery as it is to your friends and colleagues.
8. Turn off non-essential notifications
It seems as though almost every app now polls the internet in search of updates, news, messages, and other information. When it finds something, the app may chime, light up your screen and display a message, make your LED blink, or do all of the above.
All of these things consume energy.
Admittedly you likely don't want to turn off notifications about new text messages or missed calls, but you don't need to be instantly alerted that radboy84 has just bested your score at Booty Blast. Turning off superfluous notifications will help your battery last a little longer, and it will eliminate pointless distractions throughout your day.
9. Power-saving modes
Depending on your handset, you may find the manufacturer has provided power-saving features that go beyond anything available in Android (or other OSes) by default.
Enabling this mode manages the phone's various power-sapping features for you. It might, for example, prevents your apps from updating in the background, dim your screen, reduce the screen timeout setting, disable on-screen animations, and turn off vibration. By default, this mode usually turns on when your battery level drops to 20 percent, but you can set it to kick in at 30 percent instead. And the sooner the phone switches to this power-saving mode, the longer its battery will last.
10. JuiceDefender for Android
By manually adjusting all of your phone's settings over the course of a day, you may be able to squeeze a few extra usable hours out of your battery. But if the effort sounds too cumbersome to you, consider downloading an app that manages your battery for you. On Android phones, we've seen great results from JuiceDefender, which automatically toggles your radios on and off and manages your phone's CPU usage to optimize your battery life moment-to-moment.
Unfortunately there's nothing similar for iOS (that we know of), as apps don't tend to be allowed control of the underlying hardware. There are, however, plenty of apps which can tell you what's using up your battery power, and you can then decide how best to save power using this information.
Other tips for saving battery power
Hidden away in settings menus are usually plenty of options for disabling things like location services, push email, sensors or features that you never use, and more.
Most of these will make a minimal impact on battery life, but combined, they can become significant.
Instead of allowing email to be pushed to your phone at any time, why not change the setting to fetch mail every so often - maybe 15 or 30 minutes if you don't need to respond immediately to anyone.
On an iPhone 4S or 5, you can disable the Raise to Speak feature in the Siri settings, which is said to increase battery life.
Finally, as we've mentioned, it's worth rebooting your phone from time to time, rather than leaving it in sleep mode all the time. This can sometimes cure otherwise inexplicable battery draining problems.