AT&T hopes to standardize on a single operating system for AT&T-branded smartphones as part of a "dramatic consolidation" of its mobile platforms over the next few years, a company executive said Thursday.

The mobile operator believes smartphones will make up the largest portion of devices connecting to its network by about 2014, and it wants to avoid the fragmentation of platforms that has made it hard to develop mobile applications, said Roger Smith, director of next generation services, data product realization at AT&T. Speaking at the Symbian Partner Event in San Francisco, he said Symbian is "a very credible and likely candidate" to become that one operating system.

The consolidation effort is focused on a completely AT&T-branded smartphone, distinct from the iPhone and other products that may use AT&T's network, Smith said in an interview following his speech. The iPhone is actually a third-party device that takes advantage of AT&T services, such as voice, voicemail and SMS (Short Message Service), he said.

If there are AT&T-branded smartphones on many different platforms, "Whose support nightmare is that? It's ours," Smith said.

The event is taking place at a time of transition for Symbian and the whole mobile industry. On Tuesday, Nokia completed its acquisition of Symbian, the latest step in a process that eventually will make Symbian an open-source operating system under the planned Symbian Foundation. That foundation can now enter operational mode, beginning efforts such as recruitment, and Thursday's event probably is the last one put on by Symbian itself, said Jorgen Behrens, Symbian's executive vice president of marketing. The consortium, of which Nokia has been the largest shareholder, has been overseeing the operating system since 1998.

The mobile industry hasn't been effective at offering compelling user experiences, and one key problem has been fragmentation, AT&T's Smith said. AT&T has placed a lot of emphasis on Java as a platform for mobile applications but has ended up with a fragmented platform, he said, adding that the carrier hasn't managed Java well. There are many more operating systems for mobile phones than for PCs, even within a single manufacturer or carrier, and Java was once seen as a tool to simplify developing applications for all those platforms. But as in the PC universe, it has come under criticism for not fulfilling that promise.

In addition, Java doesn't allow developers to go deeply enough into a phone's software stack to deliver the kinds of experiences customers want, Smith said. So instead of trying to solve Java's fragmentation, AT&T will try to standardize on as few operating systems as possible, and preferably open platforms, he said. That will give third-party developers more opportunity to reach AT&T subscribers with mobile applications, he said.