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.

As a game, Miitomo is an excuse to collect digital objects — which can be purchased with real currency — and take photos of your Mii. Miitomo asks players questions, and their answers with friends.

“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.”

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.”

While Nintendo didn’t mention other countries by name today, it did say that “several other countries” will receive the title on the 31st alongside users in the US.