The search for an iOS developer will lead you either to the freelance market or to the market of IT companies. But I think that the freelancer exchange is not the right place for you to turn to. My advice would be to look for a good company, like https://relevant.software/hire-ios-app-developers/ , where a team will work on the application. It develops the product according to a certain methodology, and all the participants in the process interact closely with each other. It is not one freelance programmer, but a project manager, a team leader, who will always help and guide.
