Amazon Prime makes it easy to order everything from gadgets to paper towels. All those boxes sitting on your doorstep also make easy targets for thieves. Amazon Key promises to keep your orders safe by placing them somewhere the thieves can't reach: inside your house. Available in select areas, it works by connecting an approved smart lock from Kwikset or Yale with the service, which then unlocks the door for the delivery person when they arrive. The starter kit includes both a lock and an Amazon-branded indoor security camera so you can monitor deliveries, either as they happen or at your convenience.