Actually voar.io, another game by the same guy who made agar.io, was one of the first .io games. It was a gravity-survival simulator thing where you launched a rocket from Earth and tried to see how long you could stay in orbit while trying not to crash into other players (and then sometimes the moon or an asteroid would show up and forget everyone up). Unfortunately, voar.io is dead right now and while Zeach (the creator of agar.io and this) said he'll eventually bring it back, it still hasn't been done.
Also, as having bore witness to the birth of their popularity, I noticed a weird pattern where most of the .io games tend to be advertised on websites like 4chan's /v/ a lot before getting picked up by some big youtubers and getting real popular everywhere else.
#BoringHistoryStuff
