The Aqara U400 smart lock introduces Ultra-Wideband (UWB) technology to HomeKit, solving the persistent problem of unreliable auto-unlock. Unlike previous smart locks that require pulling out your iPhone or Apple Watch, the U400 uses UWB to precisely detect your location and direction, enabling seamless hands-free entry even when carrying groceries or other items.

Built on Matter over Thread, the U400 offers faster response times than Bluetooth and reduces Wi-Fi network strain. The lock supports multiple access methods including Home Key, fingerprint reader, hidden passcode keypad, and a physical keyway that can be rekeyed to match existing house keys. Aqara moved to a rechargeable lithium battery system rated for six months per charge, with a USB-C port on the lock itself for convenient charging using a portable power bank.

The Aqara U400 joins the new Level Lock Pro as a gold standard in smart locks, with PIN code management now integrated directly into the Home app. This combination of Home Key, PIN code management, and UWB technology makes Apple Home the most comprehensive platform for managing smart locks. With UWB likely to become the standard for future smart locks, the U400 represents a significant step forward in smart home convenience.