Apache is a free and open-source cross-platform web server software.
Add a respsonsive image slider to any website.
Calendly is an app for scheduling appointments, meetings, and events.
jQuery is a JavaScript library which is a free, open-source software designed to simplify HTML DOM tree traversal and manipulation, as well as event handling, CSS animation, and Ajax.
WhatsApp Business is a free to download app available on Android and iPhone using which businesses can connect with their customers.