The document discusses different types of mobile apps: native apps, web apps, and hybrid apps.
Native apps use platform-specific APIs and must be separately developed for each platform. Web apps can be accessed through a mobile browser but do not have access to device functionality.
Hybrid apps combine features of both - they are developed with web technologies like HTML, CSS and JavaScript but have access to some device functionality by wrapping the web content in a native container and allowing connections to some native APIs. This allows for cross-platform development while retaining some device-specific capabilities.