Anyone can turn a standard website into a PWA. To accomplish this, follow these three simple steps: . When deploying your site, make sure that it is served through HTTPS to control for security issues. It is also critical to ensure that it is mobile-friendly. . To translate your website into a PWA, you need to craft a web app manifest file.
Link: Ecommerce PWA: How Brands Can Benefit from Progressive Web Apps
via http://www.bigcommerce.com