Ericsson A.B., the Swedish mobile phone maker, and the Sony Corporation of Japan agreed to form a joint venture to develop and market mobile phones.

Mobility develops and manufactures mobile phones, while Motorola Solutions covers wider technologies for corporate customers and governments.

It wants to develop and sell mobile phones including smart phones and TVs.

So far none of the major cellphone manufacturers have plans to develop phones or devices to protect users from radiation.

China Mobile has signed up more than 20 handset vendors to develop phones for the Ophone OS.

Many different companies have developed phones that slide.

The Competition Other companies are developing screen-based phones.

Those companies are developing disposable wireless phones that they hope to begin selling nationwide early next year, although telecommunications experts still question whether they can be made and distributed profitably.

Citibank is developing screen-based phones to sell as part of its banking-by-phone service.

It is used to develop phones that use the OS, as well as applications that run on those phones.