GameSpy
GameSpy was a third-party technology provider of online multiplayer and matchmaking services for video games. GameSpy was a service provider for the Nintendo Wi-Fi Connection.
In April 2014, Glu Mobile (at the time owner of GameSpy Industries) announced that they will shut down the GameSpy servers on the May 31, 2014 due to integration costs and putting focus on other work. Most developers and publishers chose to continue running their own servers. Nintendo however discontinued the Nintendo Wi-Fi Connection on May 20, 2014. Nintendo instead continued development on their new online service called the Nintendo Network for the 3DS and Switch.
Despite the shut down, there were fan efforts to keep alternate online services alive. The most notable ones are Wiimmfi (Nintendo) and Revive Network (Electronic Arts).