I don't believe you need a custom chip, but HomeKit does require some advanced crypto that many low-end embedded devices probably can't support. See the depende

I don't believe you need a custom chip, but HomeKit does require some advanced crypto that many low-end embedded devices probably can't support. See the dependency list for this open source Go implementation of the HomeKit Accessory Protocol: https://github.com/brutella/hc#dependencies https://github.com/brutella/hc#dependencies Edit: Missed this line in the original article: The issue, according to Lombard, is that Apple HomeKit certification requires a co-processor to handle device authentication. That co-processor is where the device’s encryption key is stored and handles the computing associated with encryption. Looks like (for security purposes) Apple wants a dedicated crypto co-processor. Probably a tamper-proof chip that stores a private key, similar in concept to Apple's Secure Enclave.