Sierra 7C108b

A 3.1.x based firmware used for testing devices. Found on an iPhone 3GS.

Toolkit
After booting up, SwitchBoard.app screen shows up allowing you to choose different options.

They consist of:
 * ATCommand (Shown as AT Commands in this firmware)
 * BurnIn
 * LcdUTest
 * Operator
 * Soundwave

Soundwave crashes SwitchBoard.

Binaries
The firmware includes standard set of UNIX binaries. apt-get is present, suggesting that there is an internal APT repository.