Are they part of a Nintendo owned userbase? Nope. (Although if they sign up for a Nintendo account when they download the game then I would say they are)
Are they part of a userbase that contributes to Nintendo's brand awareness, drives synergy with its traditional business and postiviely impacts the bottom line? Absolutely.
Good. It was a nice move from their part.
Proud to be the first cool Nintendo fan ever
Number ONE Zelda fan in the Universe