The idevicerestore application is a full reimplementation of all granular steps which are performed during the restore of a firmware to a device.

In general, upgrades and downgrades are possible, however subject to availability of SHSH blobs from Apple for signing the firmare files.

Some key features are: - Restore: Update firmware on iOS devices - Firmware: Use official IPSW firmware archive file or a directory as source - Update: Allows updating the device by default or erasing all data - Download: On demand download of latest available firmware for a device - Cache: Downloaded firmware files are cached locally - Custom Firmware: Restore custom firmware files (requires bootrom exploit) - Baseband: Allows one to skip NOR/Baseband upgrade - SHSH: Fetch TSS records and save them as ".shsh" files - DFU: Put devices in pwned DFU mode (limera1n devices only) - AP Ticket: Use custom AP ticket from a file