Apache is a free and open-source cross-platform web server software.
Calendly is an app for scheduling appointments, meetings, and events.
Facebook pixel is an analytics tool that allows you to measure the effectiveness of your advertising.
Google Tag Manager is a tag management system (TMS) that allows you to quickly and easily update measurement codes and related code fragments collectively known as tags on your website or mobile app.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Priority Hints exposes a mechanism for developers to signal a relative priority for browsers to consider when fetching resources.
ProcessWire is an open source content management system (CMS) and framework (CMF).
UIKit is the framework used for developing iOS applications.