iTunes and the iPhone are about to have some competition on the mobile music sale market, as the upcoming T-Mobile G1 (powered by Google's new Android mobile operating system) has linked up with the Amazon MP3 store. Whereas the iPhone requires Wi-Fi to browse, sample and purchase music from iTunes, the G1 will allow users to rummage the Amazon store through the phone's cellular connection. Wi-Fi will be needed to download songs, however. The phone is expected to hit stores next month. Google and T-Mobile are also working with third-party developers that will allow users to get more out of their MP3s through additional applications.