Mobile health (mhealth) applications are transforming healthcare delivery by enhancing patient engagement and streamlining processes, but understanding development costs and essential features is crucial for stakeholders. Key cost factors include the development team, app complexity, platform choices, regulatory compliance, and integration with external systems. Essential features for mhealth apps include user authentication, electronic health record integration, appointment scheduling, health tracking, personalized health plans, and emergency features to ensure a robust and user-friendly experience.