Zillow has released an iPhone app. The app contains most of the data presented on the Zillow.com site:

• Zestimate home values, home details and historical data on 88 million U.S. homes - 95% of all homes in the country.
• Details, photos and contact info for 3.4 million for-sale listings - for sale by agent and for sale by owner.
• Data on recently-sold homes.
• Zillow's exclusive Make Me Move listings, which reflect at what price an owner would consider moving.

The iPhone app allows users to see properties in several different views: a map view, a satellite view and a list view of homes in the intended area. A profile or details page provides the Zestimate as well as a rich set of data about the property as well as nearby comps. There's also a link to the full property data set on the property on Zillow.com (which launches Safari). 

Beyond a nice user experience and interface, the thing that's really interesting and different about the app is its ability to leverage GPS. A potential use case is the following: you're taking a walk through the neighborhood and arrive at an interesting house. You don't have to enter the address to obtain Zillow's valuation; it will simply show you the data on the property you're looking at.

Here's more information from the Zillow blog and discussion on Techmeme.