Poor battery life on your mobile phone is a constant problem and it affects a lot of people. Some owners cannot get through a whole day without connecting their phone to a charger. What is wrong and what is the solution to high battery drain and short battery life? It could actually be caused by almost anything, so let's take a look at a couple of typical cases.

I noticed that my Android phone, a Samsung Galaxy S4, was warm when I pulled it out of my pocket. It could be that it is simply warm in my pocket, but it felt warmer than usual. This always triggers alarm bells in my head because when a phone is working hard, it gets hot. This is really obvious when playing games.

When the phone is working hard, it uses a lot of battery power, so the obvious thing to do is to check the battery usage. Going to Settings, More, Battery and showed that Google+ had used the most battery and it was using more than most other things combined. On opening the app, it showed nothing - no Google+ posts, updates, photos or anything like that. The app had hung and it wouldn't do anything. It was using so much battery power because it had crashed.

Battery usage . Google+

We will look at the solution in a minute, but before we do that, let's look at another example.

A couple of days later I noticed that the battery was running down very quickly. I normally get through a whole day without charging it, but by evening it was needing its charger. Visiting the Battery usage in Settings showed that this time it was the Starbucks app. (You don't still pay with cash do you? It's much easier to pay with your phone.)

You can tap an app in the Battery screen to see the app statistics. Ths app is only used for a minute or so at a time to pay for my coffee, yet the CPU total was one and a half hours! Not only that, it had received 116MB and sent 30MB of data! What on earth was going on? There's no way it should do this. Once again, some sort of crash or bug has caused the app to misbehave and it is doing things it shouldn't, like wasting battery power and bandwidth.

Battery drain . App usage

So what is the solution to these problems? How do we stop apps from draining the battery? Make sure your apps are up to date because bugs are fixed sooner or later and the next version might be better.

The best way to prevent apps from draining the battery is to shut them down. Switching to another app or the home screen just leaves them running in the background and it does not stop them using the battery power. Long press on the home button to display a list of apps in the background (some phones and tablets have a button at the bottom of the screen that performs the same action). Swipe right over them to swipe them away and it stops them running.

Long press on the home button on a Samsung phone, select the pie chart at the bottom left, then RAM at the top. You can then press Clear memory at the bottom. This clears even more background apps and services.

App manager . Clear memory

After swiping away the apps and clearing the memory, the battery usage went back to normal. There are apps that can automatically kill tasks in the background and some people swear by them, but isn't that one more app that is running in the background? The benefits outweigh the extra app that is running, but usually the built in facilities for closing apps and clearing memory work fine, so I would rather not run an extra app if I don't need it.

Keep an eye on battery usage, tap the apps on the battery screen to the see the CPU time and data transferred, and close apps and clear memory whenever you can.