Do you have a friend who works in marketing and can help you with these sales calls? Perhaps you can find someone who is willing/able to provide some of their t

Do you have a friend who works in marketing and can help you with these sales calls? Perhaps you can find someone who is willing/able to provide some of their time to help you for some potential future payout or investment in the app? Because you are trying to sell a service, I don't think it's viable to ask someone to help you for free without them having a stake in the business or receiving some sort of pay out. But I would look to friends who can help first, then branch out.