IUI may refer to:
Originally known as iphonenav, iUI was created by Joe Hewitt specifically for iPhone developers with the goal to "turn ordinary standards-based HTML into a polished, usable interface that meets the high standards set by Apple's own native iPhone apps." It gave web applications running on Safari the look of a native application built with the iOS SDK.
Currently, iUI supports most smartphones and tablets. Devices independently tested with the framework include: Palm Pre, HTC Dream/T-Mobile G1, HTC Magic/T-Mobile MyTouch 3G, HTC Hero/T-Mobile G2 Touch, Motorola CLIQ, Motorola Droid, Samsung Intercept, and all iOS devices.
iUI has been used to develop a variety of web-applications. Notable examples include Bank of America's Mobile Site and Adelphi University's Mobile Web Application Suite AU2Go.