I don't think a smartphone will be beating a Tegra X2 any time soon.
That chip is a beast and is too powerful to fit inside in a smartphone form factor without melting the inside after an hour or two.
On top of that, no smartphone game maker makes games for the upper specs. Yes a Samsung Galaxy S7 or Apple 6S have a much better processor than a Sony Vita for example, but you don't see many games that look better than Vita stuff, because smartphone games have to work with older phone versions to get a big audience.
On NX, developers will be able to focus everything on maximizing that Tegra chip, so the games you're going to get are simply going to look a lot better than the smartphone you have likely for several years.
A Tegra X2 hypothetically by the way is like 16x the power of a Vita chip. I wouldn't be surprised either if Nintendo adopts a different business model where like tablets they update the hardware. Maybe not on a yearly basis, but every 2-3 years. It would be fair since they're combined both hardware lines into one that they can have more hardware models of that said one hardware.







