Comment by eddythompson80

Save the pairing keys you get for those devices. You shouldn't need to re-request them. They are unique per device and don't change (unless if you flash the device firmware or its EEPROM or they fuck it up on an update for some reason, but they shouldn't).

Generally the only reason you'd need an app to pair a HomeKit device is if the SRP key isn't printed on the box, and as far as I know that was limited to some early devices that were shipping while HomeKit was in beta (I know LIFX lights were in that camp for example. After Apple announced HomeKit, they said that all existing lightbulbs will become HomeKit compatible through an OTA upgrade. But of course you had to use the app to get the HomeKit code)

HomeKit is a local protocol. The Apple device connects directly to the outlet or lightbulb it's trying to pair over bluetooth or through local mDNS.