A mobile application written with the platform's own tools — Swift for iOS, Kotlin for Android — and compiled specifically for that system, with direct access to every device capability.
Native is the right call when the product depends on hardware, heavy graphics, background processing, or the latest platform features on release day. It costs more because two codebases mean two of everything.
We recommend native honestly, only when the requirements justify two codebases, and otherwise propose cross-platform with native modules for the few places that genuinely need them.