Nintendo Network
Nintendo Network IDs (NNID) are user account systems for the Wii U and Nintendo 3DS, which allows players to access certain online features such as the Nintendo eShop and Miiverse. As of December 9, 2013, Nintendo Network IDs were implemented onto the Nintendo 3DS, becoming required for downloading free demos from the eShop, replacing the previous system in which eShop purchases were tied to a single system. Players who own both a Wii U and a Nintendo 3DS are able to link a single Nintendo Network ID to both systems, allowing funds added from credit cards or pre-paid cards to be shared across both systems' eShops. However, a Nintendo Network ID can only be used on one 3DS system at a time, requiring players to perform a system transfer to move account details from one 3DS system to another (IDs are currently tied to a single Wii U system, though a future update to resolve this has been promised, which is also essential for the company's long-term plans). Players may also sign into Nintendo Network on other platforms, such as the web-based Miiverse portal for computers, with functionality for tablets and smartphones also planned.