Mark Gurman / @markgurman: It's likely that the doorbell system will work with the many third-party locks already on the market that support Apple's HomeKit protocol. It's also possible that the company teams up with a specific lock maker to offer a complete system on day one. Apple entering home security is very exciting (to me). It is an area that requires strong integration across components, not just a doorbell cam. Challenge is integrating with existing world and not building a partial solution: entry, cameras, locks, glass break, water, motion, keypads, panic, contact, window, and more. PLUS monitoring. PLUS all of this should be integrated with WiFi/Threads so you don't need repeaters. Ring has done a really great job expanding. My favorite example is the "Retro Alarm" kit that integrates door ADT sensors so you don't need stick on magnets. Tons of room for great work. Simply doing faceid when we're still waiting on HomeKey isn't the killer feature I think.