Keep your phone cool and stop it overheating with these free Android apps |

Have you noticed how warm, hot even, your phone gets sometimes? Heat can be a problem and excessive temperatures can damage the internal components. Here are four Android apps to make your phone cooler.

Why do phones get hot? One reason is because they are being charged and this generates heat in the battery. The faster the charge, the hotter the phone will get.

Reducing the charging speed by using a lower powered charger will reduce the heat, but it will take many hours to charge the battery. There is a trade off between heat and speed. There isn’t much else you can do about charging heat.

The other reason why phones become hot is because they are working hard. You will have noticed that the phone is warm after playing demanding games with lots of fast action and high resolution graphics. The CPU and other components have to work extra hard during gameplay and this generates heat.

It can’t be avoided, except by not playing games.

Sometimes though, the phone seems to get hot for no reason at all. Even when it has been idle in your pocket for an hour or two. Why is this? It is because it is running background tasks and these are drawing too much power and generating too much heat.

By identifying apps that are working the system hard and closing them down, the temperature of the phone can be reduced. That’s what these apps do. They look at the background apps and services and see which are using most power, then they close them.

This means that these cooler apps are very similar to apps that extend battery life. These phone coolers will make the battery last longer in addition to running cooler.

CPU Cooler Master-Phone Cooler

CPU Cooler Master by PICOO Design is simple, but effective and has a good rating on the Google Play Store. The home screen shows an animated live scrolling chart of the phone temperature and this can be displayed in Fahrenheit or Celsius. (Don't worry about the screenshots being in C, all these apps can use F too).

There is a high temperature notification and the warning level can be set. There is an Ignore List that enables you to select apps that should not be closed.

A simple Flappy Bird style of game is included, which I found impossible to play, but maybe that’s just me. This is a good app for cooling your phone.

 CPU Cooler Master-Phone Cooler app for Android CPU Cooler Master-Phone Cooler app for Android

CPU Cooler Master, Phone Cool

CPU Cooler Master by IAP Team has a similar name to the previous app, so don’t get them confused.

The app splits the screen across the middle and in the top half is a live scrolling temperature chart. It also displays the RAM and CPU usage in the top right corner of the screen.

In the bottom half of the screen is a list of apps that are heating up the phone. Unfortunately, it appears to list every app and service on the phone, and there are dozens of them. Shutting them all down may well reduce the heat output of the phone, but it will stop a lot of things from working too.

There are tick boxes to shut down only the apps you want and fortunately this is remembered, so after the first time, using the app is a lot easier.

Some annoying ads and a tedious first use, but it gets better after that.

 CPU Cooler Master, Phone Cool app for Android CPU Cooler Master, Phone Cool app for Android

DU Phone Cooler & Cooler Master

DU Phone Cooler by DU CPU Cooler Master, is so similar to CPU Cooler Master-Phone Cooler that it makes you wonder if they are the same. There are a few minor interface differences, but it is basically the same.

That is not a bad thing and like its almost identical twin, DU Phone Cooler is a good phone cooler. It has a live scrolling temperature chart on the home screen and RAM and CPU usage indicators.

There is a button to find apps that are overheating the phone and they can be selected and closed. It is pretty good, as is the other app, and there isn’t much to choose between them.

 DU Phone Cooler & Cooler Master for Android DU Phone Cooler & Cooler Master for Android

Device Cooler -Heat Minimizer

Device Cooler by Technoapp initially offered either power saving or maximum power saving modes. One can be selected or both can be ignored to continue as normal.

The app got off to a bad start with some irritating adverts and then proclaimed that the CPU was hot when it was only 28 degrees. That’s barely above room temperature, which as 24 at the time. It certainly wasn’t hot.

There are similarities to the second app on test, CPU Cooler Master, and this one shows a complete list of everything that is running - all apps and background services. Each one can be selected or deselected and then the cooler button will close them, reducing the phone temperature.

Long pressing on apps enables them to be added to an ignore list, and the first time the app is used you have to go through a couple of dozen items selecting, deselecting and adding to the ignore list.

Once configured, the app is easier to use. The full screen ads are a bit annoying though.

 Device Cooler -Heat Minimizer for Android Device Cooler -Heat Minimizer for Android

Hot or not?

The first app on test, CPU Cooler Master-Phone Cooler, is probably the best of these, although DU Phone Cooler & Cooler Master is almost identical.

Either of these will do the job and not only will they keep the phone cool, by closing apps they should make the battery last longer too.