With the exponential growth in the usage of mobile devices (smartphones, tablets) also the amount of threats has grown. Actually, most of us forget more often the wallet at home than the mobile phone. Despite the fact that the smartphone has become a tool from which we all became addicted, many see it just as a simple tool.
Few think of their smartphone like of a powerful computer with enough RAM and storage to hold a lot of data. This important data once it lands in the wrong hands can have serious financial, personal and professional repercussions.

This is probably also the reason why very few people protect their smart devices with a security solution.
For these people and not only, here is a short list of signs that can be associated with a malware infection of the mobile device.

Signs that your smart device might have malicious software installed

1. You notice that you pay more than usual for your mobile phone bill

This is a sign that some trojan might send SMSs or make phone calls to super expensive phone numbers, sometimes even oversees. The problem with these calls is that it is very hard to prove that you didn’t manually and intentionally made them. Most of the time the mobile phone operator will ask you to pay first and then explain later.

2. Data usage increase

Malware usually sends back your private data to the cybercriminals that created it.
If you notice an increase in the data usage or if your provider is slowing down your data transfer because you consumed too much in a month, it might be a sign that malicious software communicates without your knowledge.

3. Calls are interrupted often and SMSs don’t reach their destination

Even if you see that you have maximum reception sometimes the most basic functions of the phone don’t work reliably.
Sometimes malware tries to intercept the calls and even re-route them to more expensive numbers or through proxies.

4. Battery consumption grows unexpectedly

If without using your phone more than usual you notice that the battery drains, there might be some program that is residing in the active memory. Such programs can be trojans that try to intercept the calls and SMSs you make.

5. Bad overall performance of the smartphone

If your smartphone becomes slower than usual and apps take much longer to start and function, something might be using the CPU and the memory of the phone. Review the last apps you installed and try to uninstall them to check whether one of them is consuming the resources. However, note that this might not solve your problem if you installed a malicious app. Most of the malicious apps install backdoors in your device and will download additional payload without you noticing.

6. Apps crash unexpectedly

If apps that usually worked without problems and didn’t get updated lately, suddenly start to crash, might be a sign that something is interfering with their functionality. It could also be that your smartphone doesn’t have anymore resources to run the app because something else is using it (see 5).

How to prevent infections

1. Don’t install apps from outside of the official stores

The official app stores have a process of filtering the apps and there is a good chance that malicious or simply buggy apps don’t make it there.

2. Check always the reputation of the app before you install it

There is a high probability that someone before you has tested it and ranked it.

3. Check the permissions the app is requiring. If it is too much, then probably there is something wrong.

There is no reason why a game should require you to allow it to send text messages or make phone calls. And these are just only few examples. If you notice that an app intended for something requires permissions to do actions that are not usually associated with its intended tasks then report it immediately to the store provider. Of course, don’t install it.

4. Install security software for mobile devices.

In the last two years more and more security providers have expanded their portfolio for mobile devices. Avira also has a free security tool for Android.

Sorin Mustaca

IT Security Expert