Freshservice - Freshservice: the one-stop cloud solution for all your IT management needs.
Foxit Reader - Foxit Reader is a free and light-weight multi-platform PDF document viewer.
Freshdesk - Freshdesk is a cloud-based customer support software that lets you support customers through traditional channels like phone and email, social channels like Facebook and Twitter, and your own branded community
DjVuLibre - DjVuLibre: Open Source DjVu library and viewer
Zendesk - Zendesk is a beautiful, lightweight help-desk solution.
DjView4 - Standalone viewer for DjVu files.