No longer exclusive to the Google Nexus line-up, Android 5.0 Lollipop and Android 6.0 Marshmallow is available to a variety of devices. Unfortunately, many owners of those devices are now seeing issues with poor battery life. Here are some steps you can take to fix the problem. Also see: When will my phone get Android Lollipop? | How to get new Android N now & how to downgrade Android N). 

Updated 23 June 2016 with general updates.

Poor battery life since Android update: Should I install Android Lollipop or Marshmallow? 

Before we begin we should point out that not everyone running Android Lollipop or Marshmallow is dealing with battery drain - some are really quite happy with the new OS, particularly those with devices that run stock Android out of the box. (Some are also dealing with Wi-Fi problems but, honestly, there are a lot of happy Android users out there.)  

You should also know that every new operating system comes with a few bugs that are gradually ironed out through updates as they become apparent. There is nothing inherently 'wrong' with any Android version. 

If an Android update is available for your device then it's up to you whether you should install it. No-one is holding a gun to your head. If you go ahead there are many perks, as you'll learn from our Android Lollipop review and Android 6.0 Marshmallow review, but you should be aware that there may also be a few bugs at first. 

Poor battery life since Android update: Samsung Galaxy S5 

I came across a Samsung Galaxy S5 running Android 5.0 Lollipop on the Vodafone network with such poor battery performance that it was down to 95 percent within seconds of unplugging it from the mains. The owner was carrying a spare battery with him at all times, and still he would run out of power by early evening. He also complained that his S5 was running so hot in his pocket that it was burning his leg. 

If your battery performance is this bad it's quite possible that there is something wrong with it. But the phone was functioning fine until he downloaded the latest Android update, and he is far from alone in reporting battery life issues following the installation of Android 5.0 Lollipop. 

On checking in the Battery settings what had been using his battery I found Android OS was greedier than anything else, including the display. 

It's not an issue specific to the Samsung Galaxy S5, however, so we expect to hear from more users running into battery life problems as Lollipop continues its rollout. 

Poor battery life since Android update: Android 5.0.1 Lollipop and Android 6.0 Marshmallow update 

Many Nexus 5 owners who upgraded to Android 5.0 Lollipop at launch were also plagued with battery life issues, although we've seen fewer reports of problems with those phones running the later Android 5.0.1 update which is in essence a collection of bug fixes. Google has also said the problem is fixed in the latest builds. If you haven't received an OTA update to 5.0.1 the file is available from Google; you can then check our instructions on how to install Android Lollipop on the Nexus 5. 

Unfortunately, this update might still not be available to owners of Samsung, HTC, Sony, LG or other smartphones, which in the UK are delivered OTA by the network operator, slowing down the process. However, you should double-check you are running the latest version of Android now. 

So what can you do in the meantime? 

Poor battery life since Android update: How to fix poor battery life and Android OS bug

The first thing you should check is what is actually consuming the battery. Open your Settings menu and look for a Battery or Power option; within this you should find Battery usage. Here you'll see battery consumption broken down into the various apps and services running on your phone. 

If there is a particular app that is consuming a lot of power - which can be the case with older third-party apps that haven't been optimised for newer OSes - kill it. If things don't improve following its uninstallation then you can always reinstall it.

Thanks to the tips below this article we know that many users are reporting excessive battery drain being caused by frequent Wi-Fi scanning. It's worth turning off your Wi-Fi when you aren't using it to see if this extends your battery life at all. 

There is also the well-known Android OS bug, which causes a lot of battery drain for no apparent reason. Some have pinned it down to the wakelock, which essentially prevents your phone from idling and saving power, thus consuming a lot of battery.

To help prevent this battery drain, some users suggest disabling 'Back up my data'. To disable this option, you need to locate your Back up section within your Android settings. Depending on the phone you have it can vary from its location. Once you've found the option, disable it and test the results. If there are still problems, you can always try to wipe your phone's cache (not factory reset!) - Whereby wiping the cache clears old, unused and unwanted background data that's not being used - don't worry, as long as you wipe the cache only, you won't lose any data.

To do this, you have to switch off your phone and enter recovery mode, by pressing up (or down) on your volume rocker and the power button simultaneously. We suggest looking online on how to enter recovery options for your particular phone, as it depends from different phone manufacturers. Once you've entered the recovery look for the option to clear your system cache (again, not factory reset) - and then reboot your phone. Hopefully, this will solve your wakelock issues.

Going back to that Galaxy S5 I spoke of earlier, those who have called tech support have been told a factory reset may solve their problem. And in (some) cases it has improved things, but I sympathise with those for whom a factory reset is the last thing they want to do, losing all their personal settings and customisation options in the process. Be sure to back up anything on your phone before you take this step, if you choose to do so. 

Poor battery life since Android update: That didn't work. What can I do to improve battery life? 

If all that fails then your only option to solve the problem is to wait for a bug fix to roll out to your phone. But that doesn't help you out in the meantime if your phone is all but unusable. Here are some tips to extend your smartphone's battery life. 

• Remember to restart your phone every so often. Sounds simple, but it could just be the fix you're looking for. 

• Turn down the screen brightness and adjust the screen timeout. You'll find both options in the Settings menu. 

• Turn off Bluetooth and Wi-Fi when not in use. Look for toggles in the notification bar or find these options in the Settings menu. 

• Close apps running in the background. You don't need to install a Task Manager or other app to achieve this, just tap the square button at the bottom of the display to bring up an 'Overview' or recent apps list. Running apps are shown as cards, and you can simply swipe them off the screen to close them. 

• Turn off haptics. Your phone's ability to vibrate to warn you of a new call or notification is useful, but it has to use enough power to make your whole phone shake.  

• Take advantage of power-saving modes. Some phones even have Ultra Power Saving modes that, in the case of the Samsung Galaxy S5, can make 10 percent of the battery's capacity last 24 hours by turning off inessential features and screen colours. 

• Carry a spare battery or, better yet, a power bank. Your spare battery offers a single charge for that specific handset, while you can buy a power bank that costs less and offers more charges - to any phone. Check out the Best power banks 2016. 

• Read our advice on how to charge your phone or tablet faster. 

Please add your own power-saving tips to the comments at the bottom of this article. 

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