The iphone has a hell of a lot more software running it as well as nearly 3x the processor power- there's no way you're going to get its UI and finger inputs (which is where a part of all that software and extra horsepower come in) in the 770-ever.

With that said, you're never going to install applications on the iPhone- unless apple does a reversal on it's current stand.

They're two different products aimed at two different markets with an overlap of a few features.