Amazon has launched a smartlock and app that will allow users to let package deliveries into their home remotely, ending the need to wait around for couriers.

The new service, called Amazon Key, will only be available to subscribers to Amazon's Prime delivery service. Members will be able to remotely authorise delivery services to unlock their front door using the app.

The service, for now only available in the US, could end the era of hiding keys under the doormat, or waiting at home for hours for a package delivery.

Amazon Key can also be used to schedule permanent access to family members or give temporary access to returning visitors like dog walkers or cleaners. Customers will be notified when a guest locks or unlocks the door, and the Amazon Key kit comes with a smart home camera that can be set up to monitor the front door.

For deliveries, users will receive a four-hour delivery window when a courier is arriving. When they arrive, the user will receive a notification, Amazon will verify the request through the app and the courier will unlock the door using a handheld scanner.