具有开源许可证的Sunbird版30 Boxes的替代方案

• Sunbird
  所有平台 Windows Mac Linux Chrome OS Android iPhone Windows Phone Blackberry Android Wear iPad Android Tablet Kindle Fire Web Self-Hosted Software as a Service (SaaS) SeaMonkey BSD Xfce PortableApps.com Chrome Thunderbird Sunbird iCloud
• 开源许可证
  任何牌照 免费许可证 开源许可证 商业牌照