I think it's important to understand your business goals before jumping into app development. Have you created a Lean Canvas or something like that? Do you know who the customer is and what they want? Has the developer built anything that they can show, even a mock-up or prototype? It's tempting to jump straight to building your idea, but I would caution you to think very carefully about the product/market fit first, doing some customer development, before you build too much. And, if you're on board with that approach, it's a great way to start the conversation with the developer, in terms of their willingness to also validate your assumptions before writing too much code.