Roundcube - Web-based IMAP email client
Absence - Employee vacation tracking system
Mailo - Mailo is an email client where you can send and receive emails to and from anyone with an email address.
CWS TimeOut - CWS TimeOut is an online leave tracking software or absence management solution that can also be installed on the server.
Mailpile - Mailpile is a modern, fast web-mail client with user-friendly encryption and privacy features.
PTO Ninja - Slack app helping teams better manage time off