Progressive Web Apps are user experiences that have the reach of the web, and are:

• Reliable - Load instantly and never show the downasaur, even in uncertain network conditions.
• Fast - Respond quickly to user interactions with silky smooth animations and no janky scrolling.
• Engaging - Feel like a natural app on the device, with an immersive user experience.

This new level of quality allows Progressive Web Apps to earn a place on the user's home screen.

See Google Report About PWA

Source from Google.

This work on both device chrome-Window and Chrome-Android.
Android Steps:

As the name AMP, this type of website load just in a sec from own Google server just in a click. Which site and page are enabled with AMP that have a black flash symbol at the end of the URL. you can see in image Ourkanpur.com have AMP but other sites don't have it. read more about AMP in Google AMP report.

See Google Report About AMP