Yes every gadget can be infected with viruses and some even go to the extent of crushing your phones.Some of the reasons behind viruses in phones include:
Downloading apps from the google play store that aren't protected.Most of those apps have viruses. There's this app called whaff rewards, it requires to download and test the apps.It pays well but the the results might not be pleasing and you might crush your phone and no way of reversing it .
Also,there's another way of earning through viewing ads but requires you to download an app for the lock screen. Be cautious with these,those ads might be another great source of viruses and finally downloading things from browser especially opera mini.In fact at times a message pops up saying "your android has been infected with viruses,press OK to clear the virus". The moment you'll press okay and that's now your phone will be infected.