Napster and Telefon AB LM Ericsson have announced plans to develop a wireless version of Napster that will deliver songs directly to cell phones. The companies hope that cell phone providers around the world will be able to offer Napster-branded services by the end of the year. The service will offer individual track purchases and monthly subscription plans. Cell phone providers will be able to sign up for the service and be responsible for billing and marketing it to their customers. As they become more feature-rich, cell phones are increasingly seen as competition for portable audio devices. The cell phone industry is expected to ship 70 million handsets with built-in music players this year, and the two companies hope to play an important role in the emerging market for digital music on cell phones. Ericsson is a large provider of the equipment that runs cell phone networks throughout the world, as well as a popular cell phone handset manufacturer.