Since Frances and I published a blog post last year introducing Progressive Web Apps, a healthy conversation has started about what is and isn’t a PWA. There are a lot of opinions and many shades of gray. What are the hard requirements? Which requirements are marginal? What’s aspirational? This article outlines these requirements, attempts to classify them, and provides a baseline for “what is a Progressive Web App?”
Browsers gate Progressive Web App installation prompting and badging on criteria that they detect when users navigate to sites. These criteria have been designed to ensure that sites which invoke prompts are reliable, fast, and engaging.
... read the whole story at infrequently.org.