To contest IPhone gaming I would release about 10 free mini-games on the 3DS eshop and encourage other companies to do the same. There may be microtransactions and ads, but still.
I would revive a few old franchises. They are already reviving Star Fox, so why not throw in F-Zero, Duck Hunt, Excitebike, Balloon Fighter, or Mother/Earthbound.
Then, release some crazy awesome Smash Bros 4 DLC.
Release console connection, like Sony. What is mean is if you downloaded Super Mario Bros. on the 3DS you can get it on the Wii U.
Lastly, release a new redesign of the Wii U and give it more power to keep it "next-gen".