would love to see one for the Ipad/Iphone
It already exists: Safari.
That aside, it would be nice to have more smartphone-centric apps specifically for FR, for example to provide alerts or badges on pings, FR mail, and/or state message boards. Other than that, the only other smartphone-based improvement might be layout to make it easier to select links. (Basically, a "mobile web" version of the site, which could be implemented with or without an app.)
Why? FR formats correctly on my iPod touch.