Crucially, the driver never gets a special code or key, so they won't have access to your vehicle beyond a given delivery. Amazon also checks that the driver is in the right location and carrying the right package. You shouldn't have to worry about a malicious driver using this as an excuse to swipe your ride.

The service is live for Prime subscribers in 37 cities around the US, and doesn't carry an extra charge. As with existing options like Key and Prime Now, Amazon isn't shy about its strategy here: it wants to be the fastest and most convenient option for your orders, particularly when you can't be home. And there's plenty of competitive pressure to do this -- Walmart has been speeding up its own delivery process, and it won't be surprising if in-car deliveries quickly become more than a novelty.