Nintendo Countdown Calendar is a DSiWare application initially released in North America on September 20, 2010 and in the PAL region on November 19, 2010, for 200 Nintendo Points ($2). With the Nintendo-developed application, players can track all of their events. When an event is registered, a tracker would show how many days until the event. Different icons represent different events - a jack-o-lantern for Halloween, a movie reel for a movie release, confetti for a party and so on. All events are listed chronologically.
Nintendo Countdown Calendar was first released in North America on September 20, 2010. It's unclear which Nintendo division developed the application.