Sony officially withdrew from the personal digital assistant market Wednesday, citing that PDAs were becoming passe as consumers turn to smartphones as personal information managers. The loss of Sony would mean PalmSource, the company that makes the Palm OS software, will be losing one of its biggest customers.

"The PDA market is being encroached by cell phones and other mobile devices that can offer similar functions, making it difficult for PDAs to maintain their position in the market," a Sony representative told Reuters.

Sony had the largest share of the PDA market by sales in the US last quarter with 32.1 of the market. Its closest rival was Sharp, with 19.5 percent. However, in recent months, the company has indicated it would like to focus on its core businesses such as portable music and its PlayStation line.

It is unclear what other markets Sony may exit over the coming months to align itself with this new strategy. In December, Sony indicated it may exit the plasma TV market and instead focus on flat screen televisions, where the company claims a technological edge.

Sony's exit from Japan leaves no PDA manufacturer in the country running Palm's operating system.