J-phone is the brand name of one of the big three mobile phone companies in Japan. It is currently (2001) placed third behind NTT DoCoMo and KDDI's au. Although it is trailing behind its competitors, it has recently been bought by Vodafone of the U.K. and is re-positioning to take market share lost in the past several years.

J-phone began life in the early nineties as three seperate but connected companies. The Tokyo Digital Phone Corp. was established in July 1991, followed by Kansai Digital Phone and Tokai Digital Phone, in November 1991 and March 1992. The three companies, together with companies in the Digital Tuka group, completed expansion to all of Japan with the commencement of service to Shikoku Island in February 1997. The companies were all unified under the J-phone brand name in 1999, which had until then been used only in the Kanto, Kansai, and Tokai areas.

Although all three of the major mobile companies provide the same basic types of services, J-phone was characterized early on by its comparitively low prices, and it's unique short mail services. J-phone's Skymail short mail services especially brought it popularity among younger users. DoCoMo and IDO (now au) quickly improved their text messaging services to compete. J-phone was also the first to introduce photo messaging services. With it's sha-mail service, users with camera-equipped phones can now take and send pictures by e-mail to other phones and to computers as attachments to e-mail. To compete with DoCoMo's i-mode, J-phone also offers J-Skyweb mobile internet capabilities.

In general, J-phone also offers cheaper prices for their terminals than either DoCoMo or au. While a brand new DoCoMo phone can cost more than 40,000 yen, almost all models offered by J-phone come in under 20,000 yen. However, J-phone offers less selection in phones than it's competitors. Panasonic, number two in the market in Japan, has released very few new models for J-phone, diverting its strength mostly to DoCoMo.

Like DoCoMo and au, J-phone is also planning to release a 3G mobile service based on the W-CDMA standard in 2002. In co-operation with the Vodafone parent company, J-phone successfully completed the world's first test of international roaming on W-CDMA networks, with Vodafone Spain, and J-phone aims to begin 3G service in the 23 wards of Tokyo by June of 2002. 3G service is to be expanded to cover 90% of the population of Japan by March of 2004.