The delivery fee is ultimately paid for by the customer and then taken from the total price of the order as soon as the order is placed/approved. The delivery portion of the order is collected by WOWAPPS and then sent onto the delivery partner.

Depending on the payment gateway you're using, this could be see as either 'Collected Fee, or service fee' or something similar. 

Example

If the total customer order was $50 and out of that $50, $40 was food and $10 was delivery. 

• The customer pays $50
• You (Restaruant owner) will receive $40
• WOWAPPS will receive $10 to pay the delivery partner  

This whole transaction is taken place as the order is taken and is an automatic process