There are so many great smart locks out there. But one of best models that iPhone owners should consider buying now is Aqara’s U400, which offers hands-free unlocking when you get close enough. It has Apple’s U1 ultra-wideband chip integrated to authenticate you and unlock the door hands-free, so all that you have to do is open the door when you get home. This smart lock is discounted for the first time during the Big Spring Sale, costing $229.49 (originally $269.99) at Amazon.
As our reviewer Jennifer Pattison Tuohy put it in her hands-on impressions with the U400, hands-free unlocking isn’t new — but this is the most reliable implementation she’s tried yet. Apple’s Home Key relies on a mix of Bluetooth and UWB to connect and authenticate, and you don’t need an extra app.
In addition to using Home Key, you can unlock the U400 with a code on its touchscreen keypad, through a registered fingerprint, or with a regular ol’ key. This is a Matter-over-Thread lock, and it works with your choice of smart home ecosystems. You’ll just need a Thread border router (recent Apple TV models, the second-gen HomePod, and the HomePod Mini are just a few examples of border routers at varying prices) to let your devices communicate over Thread instead of purely over Wi-Fi, saving the doorbell’s battery along the way.


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