Nintendo’s mobile debut is going well.

1.6 million people downloaded the publisher’s Miitomo social platform in the U.S. alone from March 31 through April 3, according to industry-tracking firm Sensor Tower. That number includes both iOS and Android, and it doesn’t include the days Miitomo spent at the top of the download chart on both platforms through the bulk of this week. The app, which has you answering questions that your avatar will then go off to share the answers with your friends, is now dropping down the charts. Sensor Tower has Miitomo at No. 10 on iOS. You can likely attribute some of that fall to the introduction of Disney Crossy Road, which came out yesterday. But few apps are able to keep their place at the top of the charts for long, and it’s now time for Nintendo to convert its millions of mobile players into paying customers. The publisher started making mobile games because the market is worth $34.8 billion and growing, and Miitomo is its launchpad into capturing some of those revenues.

Miitomo isn’t only out in the U.S. The game also did really well during its Japanese release earlier in March before going on to dominate the globe. But the app did see 51 percent of its installs come from the U.S., which is well ahead of any other territory. Great Britan, France, Germany, and Canada were the other top regions but they all represented less than 10 percent of total downloads each.

This is only Nintendo’s first move into mobile this year. The company is planning to launch four more games for iOS and Android over the next 12 months. Miitomo will likely serve as something of a promotional hub for those games where the publisher will alert gamers about the new releases and give them bonuses for installing them. We can also expect that the upcoming apps will feature far more traditional gaming mechanics. Miitomo is Nintendo’s take on social networking, but it’s probably going to do something that looks a lot more like a video game for the followup.