Aqara’s smart locks are known for reliable performance, but the U400 introduces something genuinely new. Its UWB-powered hands-free unlock is a legitimate step forward in convenience. The lock senses your approach and intent, unlocking the door before you even reach for the handle.

In practice, this means walking up with groceries or a child in your arms and hearing the deadbolt retract automatically. It requires a Thread-enabled Apple Home hub and an Apple Watch Series 6 or later, but for that ecosystem, it’s seamless. The fingerprint reader provides a fast, reliable backup. The lock itself is compact, at just 3 by 4.2 inches, and installs on a standard deadbolt.

Setup is straightforward, with Matter over Thread ensuring stable connectivity. Just know the full hands-free experience is exclusive to the Apple ecosystem. For those invested in it, the U400 makes coming home feel effortless.