Superhero.io
The first .io Games
Agar.io
Agar.io for iOS and Android was released on 24 July 2015 by Miniclip
Itch.io
itch.io is a website for users to host, sell and download indie video games.
Krunker.io
Twitch live streamers. Krunker.io is a first-person shooter video game (third person is available on custom hosted games).
.io
similar MMO games like it that drew from its success, notably Diep.io, Surviv.io, Hole.io, Slither.io, and krunker.io
About the .io Games
The .io domain became popular for distributing multiplayer games online for free, its use became so popular that many other websites started creating games with the .io domain to popularize their games and contribute to the escalation of free games, thus increasing the use of mobile devices.
The top level domain io has existed since 1997. The first subdomain was registered in 1998, when Levi Strauss & Co. registered the domain levi.io.
The .io domain has considerable use unrelated to the British Indian Ocean Territory.