Nintendo’s fore-ray into mobile gaming, specifically to smart devices, is here to stay. Nintendo president Tatsumi Kimishima confirmed at a recent investors meeting that Nintendo is going to continue to release 2 to 3 mobile device games per year moving forward. More than that, he expressed that Nintendo would work with other companies besides DeNA when the time is right, though the partnership between the two is going to remain strong.
Currently, we only know about one other mobile game in the works that will release later this year in Animal Crossing.
Source: Nintendo Everything