Amazon adds new US delivery function

A new ‘ Add to Delivery’ function is now available to Prime members in the US using the Amazon Shopping app or Amazon.com on mobile devices

With a single tap, members can instantly add eligible items from across Amazon to upcoming deliveries.

There’s no need to go through checkout again, and no added shipping fees. Just find what you need, tap the "Add to Delivery" button, and your item will be added to your upcoming delivery automatically.