Nintendo Wi-Fi Connection

Nintendo Wi-Fi Connection (WFC) was a free online service run by Nintendo. Several Nintendo DS and Wii games utilized the service for purposes of online multiplayer. The user merely required a wireless internet connection to connect with either system. It closed on May 20th, 2014, but it is still possible to download contents from the Wii Shop Channel and DSi Shop.

Friend Codes
The service used "Friend Codes". These were 12- to 16-digit numbers that were swapped between players in order to add each other to their friend lists within the games. In most games on the service, the only way to reliably play with a certain person was to do this. Many games also came with an "Anyone" mode which allowed the player to play with anyone who was connected, usually without functions that were present in Friend Code play (such as voice chat).

Zelda Games Utilizing the Service
was the only game in to use Nintendo Wi-Fi Connection. The purpose of the WFC in Phantom Hourglass was to use the game's multiplayer mode with another player.

Criticisms
Nintendo Wi-Fi Connection was often criticized because of its lack of many features which have become common and even expected in an online service. Features such as voice chatting were present in very few games, and the necessity of Friend Codes (as opposed to merely asking someone on a game a player has played to be added to their list) was regarded by many as a poor decision on Nintendo's part.