Standards-based technologies such as responsive design HTML5 and CSS3 and other modern web tech are the keys to web apps. They can run pretty much on any platform without any special translations or re-programming with standard-compliant web browser. Post the mobile application launch, Smartphone users can access the same app and run it just as well as on any other platform.
However, the fact is web app is fundamentally a website that can be implemented across any platform. Plus, the introduction of HTML 5 has paved way for efficiency towards functionalities and animations of the app development.
Based on the technical and content requirements of an app, further aspects and differences need to be taken into account. To have a better picture, have a look at the below mentioned important benefits of both approaches: