Bottom line: the biggest lock feature gap isn't even a Matter feature

If you’re comparing Matter-certified smart locks and wondering why some let you unlock by tapping your phone near the door while others don’t, here’s the fact that explains it: Apple’s “Home Key” tap-to-unlock isn’t part of the Matter specification at all. It runs on a separate digital-key standard called Aliro, which a lock manufacturer can support or skip independently of Matter certification. A lock can be fully Matter-certified and never get Home Key. A different lock can support Aliro’s NFC/UWB tap-to-unlock and still need a Matter-enabled Apple hub (Apple TV, HomePod, or HomePod mini) in the house to actually manage who’s allowed in. “Matter-certified” and “works like every other Matter-certified lock” are two different claims, and this is the clearest example of why.

What actually differs, platform by platform

• Google Home deliberately turns off remote and voice unlock unless the lock requires a PIN. This isn’t a bug - Google’s own developer documentation states it directly: “Remote unlock is disabled on all surfaces for Matter door locks in the Google ecosystem that don’t mandate a PIN code. Likewise, voice unlock for door locks is disabled.” If your lock doesn’t force a PIN on every unlock, expect Google Home to quietly withhold both of those conveniences, regardless of what the lock’s own manual promises.
• Apple’s Home Key (tap-to-unlock with a phone or Apple Watch) is Aliro, not Matter, and it’s optional hardware. Manufacturers can leave out the NFC/UWB radio to save battery or cost - Nuki’s own Aliro-certified keypad ships without UWB for exactly that reason. Don’t assume “Matter-certified” implies tap-to-unlock; check for Aliro/Home Key support as its own, separate line item.
• Fingerprint enrollment and advanced setup usually still need the manufacturer’s own app. One documented case: an Aqara U400 lock, added to a hub via Matter, still required the Aqara app specifically to enroll fingerprints and reach advanced settings. Matter got the lock talking to the hub for basic lock/unlock; it didn’t replace the manufacturer’s app for everything the lock’s hardware can do.
• Alexa and SmartThings’ specific restrictions are less publicly documented than Google’s. I looked for an Amazon or Samsung equivalent of Google’s explicit “here’s exactly what we disable and why” policy page and couldn’t find one as of this writing. That doesn’t mean there are no restrictions - it means you should check that platform’s own current lock-support documentation for your specific model rather than assume Google’s rules (or lack of restrictions) carry over.

The checklist for a lock specifically

1. Don’t shop by “Matter-certified” alone. For a lock, that label only promises basic multi-app lock/unlock - not tap-to-unlock, not voice unlock, not fingerprint management through the unified app.
2. If tap-to-unlock with your phone matters to you, search for “Aliro” or “Home Key” support by the specific model name - this is a separate certification from Matter, and plenty of Matter locks don’t have it.
3. If you’re on Google Home and the lock doesn’t require a PIN on every unlock, assume remote and voice unlock are off, and decide whether that trade-off (extra security, less convenience) is acceptable before buying.
4. Expect to keep the manufacturer’s app installed for fingerprint enrollment, firmware updates, or any setting deeper than basic lock/unlock - Matter pairing doesn’t retire it.
5. For Alexa or SmartThings, check that platform’s current lock-support page directly rather than assuming either Google’s restrictive pattern or a restriction-free pattern - neither is confirmed for those two ecosystems as of this writing.

Who this doesn’t fit

If you don’t care about tap-to-unlock, voice unlock, or remote unlock at all - you just want the door to lock and unlock with a code or a key fob - most of the gaps above don’t affect you, and a basic Matter lock will behave consistently across apps for that limited use case. This also isn’t a recommendation of a specific lock model; door prep (deadbolt size, existing hardware) varies enough by household that the right first step is confirming your door’s compatibility with a given lock line before comparing app features at all.

Summary

The most consequential smart-lock feature gap in the Matter ecosystem - Apple’s tap-to-unlock - isn’t actually a Matter feature at all; it’s a separate optional standard (Aliro) that some Matter locks support and others don’t. Layer that on top of Google Home’s explicit policy of disabling remote/voice unlock for non-PIN locks, and the manufacturer-app requirement for fingerprint setup, and “Matter-certified” tells you almost nothing about which unlock methods you’ll actually get. Check Aliro/Home Key support and your specific platform’s lock documentation before you buy, not after. For the general version of this problem across every device category, not just locks, see [matter-smart-home-buying-guide].