It's not easy to manage the data that is streamed to and stored on resource-constrained gadgets such as mobile phones. However, Sardana believes that Mobio's technology addresses some of the major technological challenges. For one, the data that's sent over the network is compressed by the server software so that it doesn't eat up as much bandwidth, which makes it faster to update. Additionally, only the information that's needed for a specific query is sent. For instance, if someone is leaving a movie for which he or she reserved tickets using a widget and wants to find a restaurant nearby, that individual won't need to reenter his or her location information. The data from the movie transaction is used by the application to locate the individual at that time; the restaurant widget then searches for eateries near the theater.

Mobio's widgets currently only work on phones in the Cingular, Sprint, and T-mobile networks, and only if they're Java-enabled, although the company expects that future versions of the software will be compatible with Windows Mobile and Blackberry. This somewhat limited availability highlights one of the challenges of offering Web services to mobile phones, says Daniel Dailey, professor of electrical engineering at the University of Washington, in Seattle. "It's hard to have client software run on all the phones," he says.

Sardana thinks that in the future, the widgets could take advantage of real-time location information provided by the phone. Existing applications were designed with GPS in mind, but the location-based feature will have to wait until more phones have the capability. "As more handsets become GPS-enabled," Sardana says, "then we will seamlessly blend that into our applications."