Usability 
UDR is United Dominion Realty which owns and manages a number of large apartment complexes in U.S. cities. UDR's mobile site, udrapartments.mobi makes it easy to find rental units in major U.S. cities with your mobile phone. With it you can browse by state and city or use an advanced search form that lets you filter results by price, number of bedrooms and baths and available amenities like a pool, air conditioning and whether pets are permitted.
Searches return a scrolling list of properties meeting the search criteria. There is quite a bit of information in the initial listing including address, a small photo, range of rent prices and a non-click to call phone number.You can drill down into each listing to bring up a page with a description, larger photo, driving directions, email address and click to call phone number..You can drill down to see details of all the different types of units in the building and which ones are available. For units that are unavailable you can sign up to receive text alerts to be notified when a vacancy occurs.