Native mobile apps are built for a specific platform, such as iOS for the Apple iPhone or Android for a Samsung device. They are downloaded and installed via an app store and have access to system resources, such as GPS and the camera function. Mobile apps live and run on the device itself. Snapchat, Instagram, Google Maps, and Facebook Messenger are some examples of popular mobile apps.
Web apps, on the other hand, are accessed via the internet browser and will adapt to whichever device you’re viewing them on. They are not native to a particular system, and don’t need to be downloaded or installed. Due to their responsive nature, they do indeed look and function a lot like mobile apps.