Developing an on-demand healthcare app like Zocdoc involves multiple stages, including planning, design, development, testing, and deployment. The overall investment depends largely on the complexity of features such as doctor search, appointment scheduling, user profiles, reviews, and secure messaging. Advanced functionalities like video consultations, real-time availability tracking, payment integration, and electronic health record (EHR) connectivity add further development effort. A strong and intuitive UI/UX design is essential to ensure a seamless experience for both patients and healthcare providers. Compliance with healthcare regulations and data security standards is also a critical component of the development process. The choice between building for a single platform or multiple platforms affects development scope and timelines. Backend infrastructure must be robust to handle user data, appointments, and notifications efficiently. Integration with third-party services such as payment gateways and telehealth APIs increases technical complexity. Post-launch maintenance, performance optimization, and regular updates are necessary for long-term success. Ultimately, the development approach and feature set determine the overall scale and requirements of the project.