Web-based Mobile App
Mobile web apps are web apps optimized for a good phone experience. They aren't mobile applications, but websites written in HTML/CSS and run by a browser. While they may be designed to resemble the feel of smartphone apps, they don't have much in common.
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 — and this is where the confusion arises.