If you believe your Android phone or tablet has a virus then the good news is it's really easy to delete. Here's how to remove a virus from Android. Plus, we show you how to avoid the Gunpoder virus and other Android malware. Also see: Best Android antivirus 
First of all, it's worth pointing out that it's unlikely that your Android phone or tablet has a virus. What you're more likely to be seeing is an ad that wants to convince you Android is infected and you need to download an app, or a dodgy pop-up, or perhaps your device is just misbehaving. But viruses for Android do exist. If you're sure your device has one, here's how to remove it.

How to avoid Android malware, including how to avoid Gunpoder virus

All Android viruses are delivered via apps installed on your device, so if your phone or tablet doesn't already have a virus, the best way to avoid it getting one is to never install software outside of the Google Play app store.
This is also true of the Gunpoder virus, which recently hit the headlines after Palo Alto Networks discovered it could sneak on to your phone via Nintendo game emulators installed outside Google Play - and even has the cheek to make you pay for the priviledge. Fortunately, Gunpoder hasn't been seen to affect UK users as of yet, but it's still worth taking measures to protect yourself from the Gunpoder virus and other Android viruses that may be released in the future.
To ensure you don't inadvertently install malware through the installation of apps outside of Google Play, open your Settings menu, look for the Security option, then ensure the option for Unknown Sources (allow installation of apps from unknown sources) is disabled. Also see:Security Advisor 
If you're determined to install an app from outside Google Play, do your research. Check its permissions (does a video player really need to see your contacts?), look online for reviews and have a good look at the developer's site to see what else it offers. In the case of Gunpoder, be particularly wary of Nintendo game emulator apps. 
You can also install an antivirus app, and plenty of free Android antivirus apps are available that are able to detect and remove malicious apps, for example 360 Mobile Security, Avast and Lookout. These all include an app scanner that will seek out anything dodgy, but note that these apps can also trigger false-positives - reporting an app you've been using for months as malware when you know it's fine. In most cases you can simply ignore these alerts. Also, again with Gunpoder in mind, these apps may not pick up on malicious behaviour if the app is able to hide it from them - Gunpoder uses the Airpush adware library to conceal that behaviour.