There are a few ways to get free delivery on doordash app. One way is to sign up for a doordash account and then select the 'get free delivery' option when ordering. Another way is to order using the 'promo code' feature, which will give you free delivery on your order. You can also use the 'get free delivery' option when you are signing in to your doordash account. Finally, you can use the 'sign up for doordash' feature to sign up for a doordash account and get free delivery on your first order.