Alternatívy programu Bookis pre Google Calendar s licenciou s otvoreným zdrojom

• Google Calendar
  Všetky platformy Windows Mac Linux Chrome OS Android iPhone Windows Phone iPad Android Tablet Web Self-Hosted Software as a Service (SaaS) PHP jQuery Windows Mobile Slack Microsoft Office Outlook Chrome Google Calendar Sunbird Google Apps Microsoft Exchange Server Apple Calendar
• Licencia Open Source
  Akákoľvek licencia Bezplatná licencia Licencia Open Source Obchodná licencia