Large? In terms of "lenght" or amount of content? Perhaps. Complex? You jest. NSMB is not complex, it never has been - that wasn't the point behind making the game, the point was providing a "classic" experience and it does that.I wouldn't go that far. Very rarely have I seen a mobile game that comes anywhere near as large or complex as NSMB... and that's saying something.
I'm not saying that there's a lot of "quality mobile games", but still, they are there. It's still a developing market, plus, let's not forget that it follows slightly different rules.
With "normal" gaming platforms, you get a burger for $60 and you eat the whole thing happily, with "mobile" you have a buffet of smaller starter dishes for $5 each and you mix and match, but that balance is slowly tipping as more and more quality games are released on typically "mobile" devices.