Following its launch in Japan earlier this month, Nintendo's first smartphone game/app Miitomo will debut in the United States on March 31, the company announced today.

　　The "free-to-start" game, as Nintendo calls it, was a big hit in Japan, having reached 1 million downloads in its first three days in Japan. It also reached the No. 1 spot for free apps on the App Store and Google Play.

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　　Nintendo will be hoping it can repeat that success later this week when it debuts in the US.

　　"With Miitomo, Nintendo takes its first step into the world of smart devices," Nintendo marketing executive Scott Moffitt said in a statement. "Miitomo brings the special Nintendo charm and polish that people around the world love to an entirely new format and audience."

　　Miitomo is more of an app than a game per se. Developed in partnership with DeNA, the app allows users to create and customize a Mii character, then sync up with others, much like the Mii functionality on Wii and Wii U. Users can then link their Facebook and Twitter accounts to Miitomo to find friends to interact with.

　　The core loop of Miitomo is question-answering. Here's the app's official description:

　　"Miitomo creates conversations and turns discussions into a form of play by prompting users to answer all kinds of fun questions. How would you define your fashion style? What’s the weirdest thing you've ever eaten? If you were given ten grand to spend in one day, what would you do? The answers get shared among friends, sparking interesting conversations--part of the fun is discovering unexpected facts about your friends. When users hear how their friends responded to questions, they can give answers a 'heart' or a written or picture comment."

　　The app also lets you create "Miifotos." For these, you can place Mii characters in images from a smartphone's image gallery. You can click through the image gallery above to see some examples that Nintendo provided. These images can then be shared on social media sites because the Internet needs more cat photos.

　　Although Miitomo is free to download, it also has an in-game shop where extra clothing and items can be purchased with Miitomo coins. Real-world money can be used to purchase Miitomo Coins, or they can be earned via gameplay.

　　You can pre-register for Miitomo you can sign up for a Nintendo account at the Miitomo website. Do that before March 31 and you'll get an allotment of Platinum Points for the new My Nintendo loyalty program. This new rewards program also launches on March 31, Nintendo said.

　　More images of the Miitomo app can be seen in the gallery below.

　　Miitomo is just the first of Nintendo's smartphone games. Another upcoming smartphone game "will not be a communication app" like Miitomo, but instead a title that features a well-known Nintendo character--maybe Mario?

　　A total of five smartphone games from Nintendo are due to launch by 2017. These games, all of which will be free, are being produced under the guidance of longtime Mario Kart producer Hideki Konno.

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