cdnjs is a free distributed JS library delivery service.
FingerprintJS is a browser fingerprinting library that queries browser attributes and computes a hashed visitor identifier from them.
Firebase is a Google-backed application development software that enables developers to develop iOS, Android and Web apps.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Progressive Web Apps (PWAs) are web apps built and enhanced with modern APIs to deliver enhanced capabilities, reliability, and installability while reaching anyone, anywhere, on any device, all with a single codebase.