LastCall gives your customers a short window after checkout to add products to the order they just placed — no second checkout, no support tickets. The app edits the original order, keeps your discounts accurate, and sends the customer to Shopify's own balance page to settle just the difference. Added items wait on a fulfillment hold until the balance clears, then ship with the order. You set the time window and switch it on whenever you're ready, from your Shopify admin.

• Customers add to a recent order without starting a new checkout
• Charges only the difference on Shopify's own payment page
• Keeps your existing discounts accurate on the added items
• Holds added items until the balance is paid, then ships them together
• You set the add-on window and switch it on from your admin