Cartsaver is the WhatsApp app for Shopify by Xtnd: campaigns, abandoned cart recovery, one-tap cross-sells, order updates, auto-replies and review requests in one WhatsApp conversation through the official WhatsApp Business API, plus one-tap COD order confirmation and OTP verification that mark unconfirmed orders high risk or cancel them before you ship. Built for Shopify. Free plan with 10 WhatsApp messages a month; paid plans from $9.99.