Progressive web apps are websites that function just like mobile apps without downloading and installing the software.
While web applications have been available for mobile devices from the start, they have generally been slower, have had fewer features, and been less used than native apps. But with the ability to work offline, previously only available to native apps, PWAs running on mobile devices can perform much faster and provide more features, closing the gap with native apps, in addition to being portable across both desktop and mobile platforms.
PWAs do not require separate bundling or distribution. Publication of a progressive web app is as it would be for any other web page. PWAs work in any browser, but "app-like" features such as being independent of connectivity, install to home screen and push messaging depend on browser support. As of April 2018, those features are supported to varying degrees by the Microsoft Edge, Google Chrome, Mozilla Firefox and Apple Safari browsers, but more browsers may support the features needed in the future.