Aqara has announced a new smart deadbolt lock at CES this week. The U400 ($269.99) is the first to support Apple’s Home Key’s hands-free unlocking . This uses the U1 ultra-wideband (UWB) chip in many iPhones and Apple Watches to automatically unlock your door as you approach — no physical interaction required. I tested the U400 at my home earlier this month, and it’s been a significant upgrade for my front door. I still have to physically open the door, but there’s no need to punch in a code,