Facebook pixel is an analytics tool that allows you to measure the effectiveness of your advertising.
Google AdSense is a program run by Google through which website publishers serve advertisements that are targeted to the site content and audience.
Gravitec is a push notification tool.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Phusion Passenger is a free web server and application server with support for Ruby, Python and Node.js.
Ruby on Rails is a server-side web application framework written in Ruby under the MIT License.
WhatsApp Business is a free to download app available on Android and iPhone using which businesses can connect with their customers.