mHealth (mobile health) applications deliver healthcare and wellness services via smartphones and tablets. Examples: telemedicine platforms (video consults), fitness apps (step tracking, workout logging), medication management (reminders, adherence tracking), chronic disease monitoring (glucose, blood pressure), mental health support (therapy, meditation). mHealth apps can be consumer-facing (direct-to-patient) or provider-facing (used by healthcare professionals). The field is heavily regulated: HIPAA (US), GDPR (EU), FDA (US medical devices), and local laws vary. Developers must handle sensitive health data securely, ensure interoperability with health systems, and often integrate with electronic health records (EHRs).