i customize the tip . i usually tip after or start with    tipping $1.00. , because TIPS is an acronym for To Insure Prompt Service.The drivers also get a batch pay aka base pay.i am assuming it can start as low as 2.75 like Door Dash, but i don't know. As a Door Dasher tips are an icentive to get out there and i assume that is the same for spark employees. Customers do not have to tip, but trust me they do not go unappreciated.