Nintendo revealed some details on its very first smartphone game at an investors meeting in Tokyo yesterday. Set to be released in March next year, Miitomo is a "communication application that helps friends share fun personal facts and interests," the company said in a press statement. The game features Mii avatars - used by Nintendo since the launch of the Wii - which can be personalized and will communicate with other users' Miis.

Nintendo had originally planned to release the game before the end of the year but, according to new Nintendo president Tatsumi Kimishima, the game was delayed in order to promote it. Miitomo will be available as a free download but will include in-app purchases, Kimishima said. These microtransactions will involve players buying cosmetic items for their Miis.

Precise details on how the game will actually play are still a little vague, although Nintendo says the idea behind it is to encourage people who don't like talking about themselves to reveal more to their friends. "The Mii asks you a variety of questions and communicates your answers with your friends' Mii," according to Kimishima's presentation. The game does bear a resemblance to the 3DS Tomodachi Life series, which also revolves around personalizing and interacting with Miis.

Miitomo will be the first of five releases between now and March 2017 to come from Nintendo's collaboration with DeNA, a Japanese-based games developer with a history of publishing free-to-play mobile games, including Star Wars: Galactic Defense. And while Miitomo will be a free download, the four other releases will be traditional paid games.

Fans will likely be disappointed to find out that the first smartphone game from Nintendo is a social media-like app that won't feature any of its iconic characters, but the company may just be testing the mobile-gaming waters with Miitomo; it would be a surprise if Nintendo didn't bring some of its famous IPs to the mobile platform at a later date. Kimishima did say, however, that Nintendo does not expect mobile games to account for even half of its revenue, and that these games are intended to drive new customers to its hardware and software.

News of Miitomo and its delay to next year caused Nintendo shares to fall by almost 9%, while DeNA's shares were hit even harder, plunging 15%.

Expect more information about Miitomo to be released over the coming months.