Which means all online functionality for past and future titles, like Mario Kart 8, Splatoon 2, and Super Smash Bros. Ultimate, will go behind the subscription paywall as of September 19 - next week. But, compared to its contemporary services like Xbox Live and PlayStation Network, the AU $29.95 for 12-months is pretty cheap.
And will offer cloud saves, access to select NES titles rebuilt for online play, and access to a dedicated smart phone app for social functionality.
Weirdly, not every title will offer cloud save functionality - which feels like one step forward and another half step back. Especially as it means saves and progress will be tied to hardware and not a paid-for online account.
Anyway, Nintendo will also be offering a free-trial week for Nintendo Switch Online - so players will get to test out the new app and other features.