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.
A modest JavaScript framework for the HTML you already have.
TinyMCE is an online rich-text editor released as open-source software. TinyMCE is designed to integrate with JavaScript libraries, Vue.js, and AngularJS as well as content management systems such as Joomla!, and WordPress.
WhatsApp Business is a free to download app available on Android and iPhone using which businesses can connect with their customers.