As we’ve seen, Android is really exploding onto the scene right now with many people in the UK buying the HTC Desire as their first Android device.  Although, as you would expect, everyone is loving their slick 2.1 experience on such a great handset, the main complaint I hear is about the battery life.  So, with that in mind, here are some tips to get the most from your Lithium-ion battery.  These tips are taken using a Nexus One running Cyanogen 5.0.6.  Some settings might be slightly different on your device.

1) Automatic Brightness

Although it would seem battery usage stats on the Desire look like they lie, the display takes around 70% of battery life during average use.  To ensure you use a minimal amount, go to Settings –> Sound & Display –> Brightness and tick Automatic Brightness.  This will adjust your screen brightness to match the light levels of the room/area you’re in.  In dark rooms the brightness is dropped down as you don’t need it high.  In sunlight it’ll crank it up for you.

2) Limit your data

The next biggest drain on your battery is your data usage.  It’s a lot harder than you would think to stop your phone using it’s 3G or HSDPA connection.  You could just lower all the update settings on apps you use.  Check your e-mail every 2 hours, check weather and news every 12 hours, Facebook and Twitter updates every 4 hours maybe, but generally you’re going to need an App that will actually change your APN (Access Point Name) settings so the phone simply can’t access the net.  One option would be JuiceDefender. You can set a variety of settings to suit your preferences, but the idea of the app is, when the screen is off, it kills your connection and will only open it for a minute every quarter of an hour to enable updates and e-mail checks to be performed.

While I have found this works well, it also caused problems in that it didn’t always return my connection to normal on turning on the screen.  Another option would be APNDroid which is a simpler widget to turn on and off your APN.  To give you an idea, the times my connection was closed, I would get 1½ to 2% drain every hour.  In theory this would make my Nexus One last 2 days or more…  I recall my Hero once lasted over 3 days as I turned data off totally!

If you don’t fancy killing your connection totally, you might want to just switch to 2G only.  Go to Settings –> Wireless & Networks –> Mobile Networks and select ‘Use only 2G networks’  You will probably find a whole plethora of apps on the Market that will switch between 2G and 3G at the press of a button.

3) Task Killing

Although some prominent Android developers have recently come out against these, most people still believe they have beneficial results on battery life.  Killing apps running in the background, or more importantly killing services you don’t need is a good way to use less juice.  Be careful what services you kill though.  If they come straight back, there’s a good chance you should set them to ‘ignore’.

**UPDATE 29/10** With 2.2, this is now considered a bad idea and you probably shouldn’t use one.  More power is consumed killing and then them starting back up than saved by them not being sat in memory.

4) Control Your CPU (root only)

If you have a rooted device, SetCPU is a great app that will lower your CPU speed when the phone goes into standby.  This will of course save battery. Take a look at our video review too.

5) Undervolting (root only)

This one’s for those of you that like to meddle with your phones and not recommended to new users.  This thread on XDA Developers shows how you flash a new kernel onto a Nexus One, which uses a lower voltage for the CPU and overclocks it at the same time!  Of course a lower voltage means less power used.  Once again, be sure you know what you’re doing before you try this!

6) WiFi, Bluetooth and GPS

Make sure you have your ‘Power Control’ widget on a home screen and turn things off when you don’t need them.  I use WiFi Status to remind me when I don’t need WiFi on (when I have no connection) and Bluetooth Power Profile (Paid app) to automatically turn on Bluetooth when a power source is connected and turn it back off when the phone is unplugged.  This is great for me as I connect to my car stereo for music and calls.  When at home, if you have WiFi you will probably find you want to have WiFi on the whole time as it’s more efficient than the phone using it’s data connection.  Go to Settings –> Wireless & Settings –> WiFi Settings –> Menu –> Advanced –> WiFi Sleep Policy and set it to ‘Never’.

7) Live Wallpapers

If you’re on a Desire or Nexus One, you’re probably really enjoying the gorgeous live wallpapers.  Just bear in mind, they do use more battery!  You might find some use as much as 5% of your battery, just to make it look nice.  If you really want to go to an extreme, logic dictates that a dark background/wallpaper will use less battery because of the reduced screen brightness.  Small numbers, but it could give you an extra hour when you really need it!

Less widgets

In a similar vein to number 3, using more widgets on your home screen will use more power.  Live widgets (those that adjust in real time) use crazy amounts of power.  Try adding a Task Killers live widget, one press kills apps, but it will take maybe as much as 20% of your battery!  Most widgets have some kind of update or live service, so of course it will use more data and more power.

9) Condition your battery

There are many different opinions on the net these days, but the ones I believe tell me to not let this type of battery run completely dry.  Each time you do this, it will run slightly less from full charge next time.  Instead, once a month, run it down to 20%, turn the phone off, remove the battery and then reinsert it.  Don’t turn the phone on but charge it until the light goes green and then for 2 hours more (overnight is good).  Turn on and use…

10) Turn off haptic feedback

Head to Settings –> Language & Keyboard –> Android keyboard and untick ‘Vibrate on keypress’.  This will save you a surprising amount of battery.

Hopefully these tips will help you extend your battery life somewhat.  If you have any tips of your own, post them in the comments below.