Alternativ till Mark the meeting för Google Apps med gratis licens

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  Alla plattformar Windows Mac Linux Chrome OS Android iPhone Windows Phone iPad Android Tablet Web Self-Hosted Software as a Service (SaaS) jQuery Windows Mobile Slack Microsoft Office Outlook Chrome Google Calendar Drupal Google Apps Microsoft Exchange Server Apple Calendar
• Gratis licens
  Eventuell licens Gratis licens Open Source-licens Kommersiell licens