1. RoamBi
Probably the most useful of the applications listed here, RoamBi is a powerful tool that turns your data into dynamic visualizations on the iPhone. RoamBi works with several data sources, like Excel, Salesforce, Crystal Reports, WebIntelligence, and others; turn the data into a RoamBi View, and view, analyze, modify or share RoamBi visualizations directly from your iPhone.
This demo shows Ziostation 3D, a system that renders high resolution CT images on a remote server. You can access the server from the iPhone, and view and interact with the rendered images in real time. The application, although in proof-of-concept stage, makes full use of the iPhone's multitouch interface with some amazing results.
3. Audiogasm
Anyone who was ever hooked to WinAmp's old-school visualizations will love this one. Audiogasm is a powerful visualization tool that uses the iPhone's microphone to visualize music in real time. You can shake the iPhone if you want to switch to a different animation, and you can save the current image to your iPhone, and set it as wallpaper at any time.
4. iGrapher
iGrapher is an iPhone optimized stock market data analysis tool that lets you create visual graphs and comparisons for indices and stocks on the market. It still has a long way to go before it becomes usable in real life, but it promises a lot of neat features, including 3D data visualizations, in the future.
This one is really something else. Augmented Reality is a system that enables you to explore a 3D virtual world using special visual markers. In the video below, the user explores a 3D environment that shows various aspects of the Star Trek ship U.S.S. Enterprise, including its exterior, interior, warping etc. You can print the marker on a piece of paper, or you can download a special image on your iPhone, and place it in front of your webcam, and you can behold the Enterprise in all its 3D glory.
See another video that shows how Augmented Reality can be used on the iPhone here.