They never said anything about piracy. Android version is coming sometime in 2017. Most likely Apple simply paid for timed exclusivity, but Nintendo did say since there are fewer iOS devices, it was easier for them to test the game.
My expectations are firmly in check- all they've shown is a bunch of games that look indiscernible from their Wii U equivalents, and a likely completely bullshot feed of Skyrim.
And today Eurogamer has a report saying the machine isn't using the full spec of the Tegra X1 in either console or docked mode, so they can hit battery and thermal targets.