Orange, a telecommunications operator in Europe, has had a store for years, said Steve Glagow, vice president at Orange Partner. But he saw a down side to the proliferation of such stores.

"I struggle a little bit with all of the announcements of all the application stores because there's a plethora of choice out there for the end consumer. And in a sense, it creates a little bit of confusion in terms of where do they go to find what they're looking for," he said.

An app store, though, helps a consumer build an affinity toward a handset, he said. "They actually keep it for a longer period of time," Glagow said. It is difficult to search 25,000 applications via a small handset device, so Orange can present applications that fit a customer's profile, he said.

Sony plans promotion efforts for applications. "We're really going to try and be very active in promoting applications within our store that we decide are going to be fantastic ones," said Bill Maggs, head of developer and partner engagement for North America at Sony Ericsson.

"[The store] will not be a gigantic catalog with a search engine," he said.