But don't expect nationwide in-home deliveries just yet.
A handful of Amazon Key's main features are being rolled out across the US.
That means you can now use the service anywhere in the country for keyless entry, remote lock and unlock, and guest access, the company said Thursday. Plus, five more locks now work with Amazon Key, for a total of eight locks available for Amazon Key customers.
But if you were waiting for in-home delivery using Amazon Key, that's not part of the expansion. In-home delivery will still only be available to Prime customers in 37 US cities and surrounding areas.
Amazon is hoping to use Amazon Key to make itself an even bigger player in smart home technologies, with the company already dominant in smart speakers through its Echo brand. Amazon is focusing on the smart home so it can sell its Prime members new security cameras and smart doorbells, and hopefully convince them to use their Echo speakers for more voice shopping.
The company, though, faces loads of competition in the new market, particularly from Google, so it's moving aggressive to keep expanding and introduce new features. Amazon since December has acquired two smart doorbell companies, Blink and Ring, and has rolled out new Echo devices to stay one step ahead of rivals. It's also had spats with Google over Nest, Google's own smart home business that's also partnered with Amazon.
Amazon introduced Amazon Key in October as a system that includes a smart door lock, its own Cloud Cam security camera and the Amazon Key app. Using these elements, people can open and close their doors without a key or give a guest a code to enter their homes. But the most interesting -- and controversial -- part of Amazon Key is its in-home delivery capabilities, allowing delivery people to open your door, slide packages inside and then lock the door.
Besides deliveries, Amazon said the service can eventually be used for in-home visits from local businesses on Amazon Home Services, including house cleaners and dog walkers.
The service may help people avoid rain-soaked packages or parcel theft from their front stoops. Plus, it may introduce a whole new way of using home services like plumbers and cable repair workers. But the response from many in the public was that Amazon was asking too much of its customers to allow it to open their front doors.
As is typical of the secretive company, Amazon hasn't disclosed any specific figures on how many customers have adopted or used Amazon Key.
In addition to the nationwide rollout of some features, Amazon Key on Thursday added new locks from Kwikset and Yale. It previously offered just three locks for the service from those two lock makers.
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