Aricent today said it has begun selling its Celltop widget-based user interface software worldwide, ending the exclusivity Alltel had on the platform. The mobile software developer said it has retooled the platform for Java as well as BREW and is conducting global trials with operators.

Celltop is mobile phone client platform that embeds applications in individual widgets in the phone's user interface, allowing customers to highly personalize the content on their home screens. Celltop essentially allows for multiple home screens, allowing customers to rapidly scroll through applications such as stock tickers, sports score trackers, weather screens and news portals, all of which are updated in real-time through the phone’s data connection. Gradually Alltel and Celltop have added new widgets such as XM Radio and video streaming through an open developer program.

Alltel launched the Celltop software in January 2007 to much acclaim and has since embedded the software stack on the majority of its data-capable feature phones. Alltel does not break out data revenues and hasn’t released any statistics on the number of customers using Celltop, but Alltel officials have repeatedly said they are pleased with the service. Aricent, however, said that uptake on services such as ringtone downloads and SMS has been much higher when customers access them through Celltop widgets than industry averages.

Head of business units for Celltop Sajal Gupta said that Aricent has been free to sell the platform to other providers since last year, but decided to go back into development to increase Celltop’s reach. “We gad to make it available on the uiOne globally, but after talking to potential customers, we decided to make it available on Java,” Gupta said.

The Java platform has allowed Aricent to land trials with at least three commercial operators, one in Asia, South America and Europe respectively. So far Celltop is only in lab trials but the results have been encouraging, Gupta said, and Aricent expects them to move to network trials soon.