.BBFW File Extension

A BBFW file is a firmware file used to update an iPhone or other Apple device's baseband processor. It is a Zip-compressed archive that contains multiple .PLIST and .MBN files. BBFW files are distributed and installed using iPhone .IPSW files.

A baseband processor is a chip that manages a device's cellular and radio functions. Each iPhone, Apple Watch, and iPad that can perform cellular functions includes a baseband processor.

Periodically, Apple updates baseband processors' firmware using BBFW files. These files are distributed within normal iOS and watchOS updates. As such, most Apple device users will never encounter a BBFW file. However, those who have jailbroken their devices, so they can manually manage their devices' firmware, may need to manually install a BBFW file as part of their firmware update process.

BBFW files are not meant to be opened. However, those who use the futurerestore app (cross-platform) to upgrade or downgrade their iDevice's firmware can manually specify what BBFW file they want to use while overwriting their device's firmware.