Amazon (AMZN  ) can now ensure that packages are delivered securely and straight into your living room, even if you're not home.

The online retail giant's latest innovation, Amazon Key, functions almost exactly as one might expect from its name. Customers who purchase Amazon Key will receive a $250 kit that includes an indoor HD security camera, a smart lock, and free installation. Once Amazon couriers attempt to scan the barcode of your ordered product to deliver it, Amazon verifies that they are at the correct location through encrypted authentication, activates the camera, and unlocks your door so that the courier can drop it off inside. No access codes or keys are given to the couriers. The security camera, which is synced with Amazon's digital voice assistant, Alexa, is there to ensure that nothing nefarious goes on; you can either watch a replay of the delivery later or stream it live as it is happening through the cloud.

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Amazon Key's use isn't limited to delivery of purchased products. You can replace your physical key altogether by using the Amazon Key function to grant family and friends access to your home for a one-time, temporary, periodic, or permanent basis.

Amazon Key is the online retail giant's most recent foray into customer convenience. It is only one small part of a plan to introduce a vast array of over 1,200 services from 60 different professions over the next several months. These services will range from dog walking contracted through Rover.com and home cleaning provided by Merry Maids. The service providers will all be able to gain unattended access to the home to perform these services by means of Amazon Key.

Some have expressed concerns about safety and privacy. There is resistance to the basic idea of allowing a stranger into a home when no one is present, and doubts about leaked camera footage or failed servers. The presence of another recording device in the home compounds the problem posed by Amazon Echo and Alexa, which records and stores audio from inside of private homes and has raised First Amendment issues.

© Amazon

Amazon has not commented on these concerns. Amazon's Chief Financial Officer, Brian Olsavsky, has only said that the introduction of this service is "mostly about increasing convenience for the customer." Peter Larsen, the Vice President of Delivery Technology, has suggested that Amazon Key will give customers "peace of mind," but only insofar as their packages have been successfully delivered in their absence. Amazon has attempted to ensure customer satisfaction by providing its Happiness Guarantee, which will compensate customers who are not satisfied or are actively harmed by the Amazon Key delivery process.

These anxieties have not been significant enough to harm Amazon's shares, which recently soared by more than 7 percent, or Amazon's overall revenue, which has grown by 34 percent in the third quarter. The innovations Amazon produces come with a hefty price tag, however, and partly account for why Amazon's profit margins remain slim.