APPLE INSIDER
Ahead of the official App Store SDK, Scott Forstall told Pandora to use jailbroken iPhones to develop their music app.
PandoraLong before he left Apple, and has proven hard to track down, Scott Forstall promoted the then forthcoming App Store to developers. Music service Pandora’s chief technology officer, Tom Conrad, says around 2007, that included advising them to start work early using jailbroken iPhones.
Source: APPLE INSIDER