The new device will give O2 music fans the choice of using the SX1 with an integrated digital music player, or a mobile with a separate device to search, preview, download and play full music tracks over the O2 mobile network.
Earlier this week, T-Mobile unveiled a new range of handsets it is calling Ear Phones, which will let T-Mobile subscribers download and listen to music over the network.
The Siemens SX1 comes with a 128MB memory card capable of storing up to 128 full-length tracks, and boasts features including a video and audio player, FM radio and tri-band functionality.
The launch follows O2's over-the-air music download service, introduced in November 2003 with the standalone O2 Digital Music Player, which offers 100,000 full-length tracks through partnerships with Sony Music, Warner Bros, Universal, BMG, AIM Independents and MTV.
O2 has also recently launched an artists and bands service featuring official mobile sites for names such as Outkast, Faithless and Dido, with more to follow. Downloads include ringtones and "truetones", with video links to be added soon.
Megan Forster, music marketing manager at O2, said: "O2 is stepping out as the clear leader in mobile music with more music content and services on offer than any other network. This is a combination of the launch of Europe's first mobile downloads service and the great range of music information and downloads offered through our O2 Active Wap service."
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