Everyone who gets a Nintendo Account before launch will also get free Platinum Points for the My Nintendo rewards program launching alongside the app. According to the preregistration notes on the website, the points can be exchanged for rewards through my Nintendo - however, the preregistration Platinum Points will expire 6 months after the service launches.

As for the app itself, Miitomo is apparently a social game which uses Nintendo’s Mii characters, which can either be built from scratch, created from a photo, or imported from a Wii U or Nintendo 3DS using a QR code. Miitomo users will then be given a series of questions, the answers of which will be shared with their friends in the app. Friends can “heart” or comment on the answers.

Users can also earn Miitomo coins which they can use to purchase special outfits for their Mii. There will also be a Miifoto feature, “which lets them put their Mii characters in fun poses with cool stamps, or by combining their Mii image with photos they have taken themselves. These creations can then easily be posted to social media services like Instagram, Twitter and Facebook.”

Basically, the whole thing sounds like a souped-up version of the existing StreetPass feature on the Nintendo 3DS, except that you interact with friends rather than randomly-encountered strangers. Whether or not this appeals to a high number of users remains to be seen, but it may be difficult for the app to distinguish itself from the existing social networking options available.