What is "slither.io"

Slither.io is a massively multiplayer browser game developed by Steve Howse. Players control a snake-like avatar, which consumes multicolored pellets from other players, and ones that naturally spawn on the map in the game to grow in size. The objective of the game is to grow the longest snake in the server. Slither.io is similar in concept to the popular 2015 web game Agar.io and is reminiscent of the classic arcade game Snake. The game grew in popularity following its promotion among several prominent YouTube users such as Pewdiepie. A mobile version of the game for Android was released on March 27, 2016, and topped the App Store shortly after its release.