When you connect a third-party product to an Apple product such as an iPhone, you can immediately recognize it and use various functions because it is a product that complies with various established protocols. One protocol is iAP2, which allows third-party accessories to access the functionality of Apple products such as the iPhone.
iAP2 was originally defined as “iAP (iPod Accessory Protocol)”, a protocol for data communication with iPad accessories. It is developed as “Interface Accessory Protocol”, and the functions are further expanded to the latest specification iAP2.
iAP2 adds music data (song data and metadata such as song name / artist / cover art) from Apple devices such as iPhone, content similar to iAP such as photos and videos, and data handled by in-vehicle information systems between devices. You can communicate at high speed.
When an iOS app communicates with an external accessory, use the External Accessory framework. iAP2 is also available in this framework and is used in various apps / external accessories. iAP2 is also used when sending route information of maps searched on iPhone to CarPlay (in-vehicle system) via Bluetooth.
To support iAP2 in accessories, accessory developersApple MFi licensing programAs well as the required MFi hardware (IC). The details of the specification are not disclosed to the outside, and in that sense, it is a function not directly related to the end user.