NewEgg – Wireless Radio:GSM 900/1800/1900 MHz, Compatible Carrier & Service:AT&T, T-Mobile, Wi-Fi Support:IEEE802.11b/g, Data transfer:GPRS, EDGE, Wi-Fi, Audio:Windows Media Player supported formats: AAC, AAC+, eAAC+, MP3, WMA, WAV, QCELP, MPEG4, AMR-NB, AMR-WB Built-in microphone and speaker, Additional Function:Wi-Fi/Music, Operating System:Windows Mobile 6 Professional