Google Analytics is a free web analytics service that tracks and reports website traffic.
Heroku is a cloud platform as a service (PaaS) supporting several programming languages.
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.