Doctors clinic management mobile app

I'm looking for a skilled freelancer to develop a mobile app to optimize the management of my doctors clinic. I don't have a specific design in mind, so I'm open for suggestions. The app should have a specific set of features, including appointment booking, patient records management, and billing and payment processing. I will also need both an Android and an iOS version of the app for maximum coverage. If you have the expertise to deliver great results and solid experience with mobile app development, I'm interested in hearing from you.