I'm not developer 😅 ... so I can not share with you tech details of how to build a Progressive Web app but I want to explain what are the advantages of using these technologies thinking in product and business.
We can say that a PWA is a mobile web that deliver an app like experience
Web capabilities are evolving more and more what allow bring a friendly interaction for users and therefore a better user experience. Said that, what are the advantages?
Less code, more channels
Regular website: From your ".com" site you can bring the full product experience with no donwload or redirection required, acquisition friendly.
Apps stores: You can publish your product on any of most common stores, Google Play from Android devices and App Store for the Apple ones. It requires a small adaptation.
Desktop app: If your product could work as an app for desktop you can also adapt your pwa code to built it (Slack is made with js techonologies).
And all with the same code! You can reduce drastically the effort required to build and mantain your digital product.
Less friction on acquisition
It's not necessary to redirect users to the stores for download your app nor any other additional step to user your product. Think that the regular app stores click funnel cause about a 30% of dropoff... Avoiding the store you can optimize the money invested on acquisition.
Same engagement as an app
When you enter to a pwa product url, the browsers show you the option to add a launch icon to your desktop. It means that user can open your pwa from their smartphones without open the browser.
Another awesome advantage of building pwa products are the push notifications. Now almost all browsers allow websites to send push notifications to the users, that's a super good channel of communication with the users.
Using pwa technologies are, in my opinion, is the best way to validate products on the early stage, in a couple of months you can develop a functional web app ready to be scaled, and just maintaining one code.
That's what I've experienced from more than 2 years working on different pwa based products, in different stages of the company lifecycle and different business models.
I attached a list of related articles for giving you more info about the progressive web app world: