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You should install antivirus on your Android smartphone, but which one?

If your Android device isn't getting updates, then the very least you can do is download and install a security app. But which one should you install?

Yesterday's piece on "What should you do with an old Android smartphone" generated a lot of comments. Because I recommended installing a security app, one of the most popular questions was, predictably, which one?

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That's a tough question.

It's tough because testing security apps means throwing existing vulnerabilities at it, which doesn't tell you how well it will handle future vulnerabilities. Another issue is that it's impossible to gauge what kind of performance hit that the app will have across the myriad of devices out there.

So, this is what I suggest you do.

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Try more than one.

Before I go any further, let me warn you that there are a lot of fake security apps out there. On top of that, there are ones that do little to nothing. Whether you go with something on this list or something different, I suggest you don't venture away from the big names, the same names who were making security apps for Windows systems a decade ago.

Venturing too far off the beaten path could very well result in you installing the very same badware on your Android device that you are trying to avoid.

Here's my list -- it's quite short -- of recommended apps. There are three free apps here and one paid-for app. I've run all of them on a variety of devices and have been happy with the results. 

Sophos Intercept X for Mobile

Price: Free

Why do I like this: No ads! That's a rarity when it comes to free security apps. It's not as flashy or whizz-bang as the other apps, but it has scored amazingly well in the AV-TEST testing and gets the job done.

View Now at Google Play Store

Kaspersky Antivirus: Security, Virus Cleaner

Price: Free

Why do I like this: A solid, easy-to-use app. It does show ads, but I didn't find them intrusive.

View Now at Google Play Store

Avast Mobile Security

Price: Free

Why do I like this: Another app that got the job done. Again, it does show ads, but I didn't find them intrusive. It also has features such as "Boost RAM" that you can play with. 

View Now at Google Play Store

Bitdefender Mobile Security & Antivirus

Price: $14.99 for the first year

Why do I like this: Gives you great protection from malware with the least impact on system performance (as tested by AV-TEST). My only gripe is that the VPN came with unlimited data rather than the 200MB/day, which feels low.

View Now at BitDefender

Bonus.

Quite a few people have asked me what VPN I use. It's the same one I have been using for years, and none of the others I've tested has come close to it in terms of awesomeness.

F-Secure Freedome

Price: From $34.99 per year for 3 devices

Why do I like this: It's fast, easy to use, and I've put terabytes through it across many countries without any problems at all.

View Now at Google Play Store

Do you have a security app installed on your smartphone? If so, which one? Let me know in the comments down below.