Apple open-sources HomeKit Accessory Development Kit to spur adoption, grow new standard

Apple's Home app

Portions of the HomeKit Accessory Development Kit (ADK), tools used by vendors and accessory makers to build HomeKit-compatible devices, were posted to GitHub by Apple on Wednesday, the company announced in a post to its developer webpage.

The HomeKit Open Source ADK can be used by anyone to prototype smart home devices. Ambitious users who want to build HomeKit devices for their own home can use it get started, for example. Accessory manufacturers can also use the open-source ADK to test products before formally joining the HomeKit MFi program, enabling proof-of-concept evaluations before embarking on the laborious and expensive process of becoming an MFi partner.

Apple notes individuals and companies planning to sell HomeKit-compatible accessories must use the commercial version of the kit supplied by the Apple MFi program. Still, providing open-source access to key bits of code hints at a major shift in the tech giant's smart home strategy and could ultimately boost the number of HomeKit contributors.

Apple released the Accessory Development Kit for partners in the MFi program in 2018. Contained within the ADK is the HomeKit Accessory Protocol, a part of the HomeKit accessory logic that communicates with the HomeKit platform. Apple made this available to all developers with iOS 12 that same year.

Since then, companies or individuals looking to test out HomeKit only had access to the HomeKit Accessory Protocol and were responsible for all of the accessory logic, adopting the protocol and much more. For those in the MFi program, the ADK stripped away much of the hassle, greatly simplifying the process.

At the time, Apple said with the ADK a functional prototype device could be created within a week and companies would be able to bring an accessory to market in as little as three months.

Now, the ADK is available to everyone, not just those in the MFi program.

On Wednesday, Apple announced the formation of Project Connected Home Over IP, a consortium of companies that hope to develop an open standard that allows manufacturers to more easily build devices that work on multiple smart home platforms and assistants. That could include platforms such as Amazon's Alexa as well as Apple's HomeKit.

Apple said it open-sourced its HomeKit ADK "to accelerate the development of the new universal standard." Further, the company also plans to contribute the HomeKit Accessory Protocol to the working group.