Core Points - Amazon has launched a new service called "Add to Delivery" for Prime members in the U.S., allowing them to add additional items to existing orders that have not yet shipped without creating a new order [1][4] - The feature is currently available only on the Amazon App and Amazon.com mobile site, and is limited to eligible products such as electronics, clothing, books, and groceries [1][4] Group 1 - The service is being gradually rolled out after testing with select Prime members [4] - Users can easily identify eligible products by a new blue "Add to Delivery" button appearing below the standard yellow "Add to Cart" button for items that can be delivered later the same day or the next day [4] - If users accidentally click the button or change their minds, they can immediately use the undo option to remove the item from the order [4] Group 2 - Amazon aims to enhance shopping convenience and adapt to real shopping habits, where consumers may have spontaneous needs [4] - This feature is particularly useful for users who often remember to purchase important items only after completing their orders [4] - There are no additional shipping fees for the added items, but users must pay the Amazon Prime membership fee, which is $14.99 per month or $139 per year [4]