Links created with the Checkout API don’t open the Square app. They allow the customer to make a payment on a Square hosted page. If you want to open the Square app and process payment you’ll need to use the Point of Sale API. 
Links created with the Checkout API don’t open the Square app. They allow the customer to make a payment on a Square hosted page. If you want to open the Square app and process payment you’ll need to use the Point of Sale API.