The curious case of the .io genre began in 2015 with a single game going by the name of Agar.io.

So named for its cell-like theme ('Agar') and the top-level domain name it existed under in its initial web browser guise ('.io'), Agar.io provided a blissfully simple, massively multiplayer online experience. The idea here was to gobble up smaller cells to make your own avatar bigger, with some of those smaller cells taking the form of your fellow players.

In the wake of its huge success (aided no end by swift Android and iOS ports), a string of games inspired by Agar.io popped up. And thus the .io genre was born.

We now have ourselves a thriving little .io sub-genre, filled with games that have begun to stretch the form in new directions.

With that in mind we thought now would be a good time to round up some of the best and most popular .io games on the Google Play Store. Is you favourite missing from our list? Let us know in the comments below.

Happy hunting.