The cost of app development is fairly expensive since the app development process includes BaaS (backend as a service) and API (applicatio program interface). A team of experts will be required to develop different aspects for a mobile app. Personnels include UX designer/programmer, project manager, iOS/Android app developers, server developers, graphic designers. If you wish to have CMS (content management system) in your app, the cost will increase by half. Increasing number and complexity of the required features in the mobile application shall increase the cost accordingly.