通信1.2kGPL-3.0FreeBriar为活动人士和记者设计的去中心化消息应用，支持离线点对点通信e2e-encryptedprivacy-focuseddecentralizedAlternative to: WhatsApp, TelegramExplore
通信8.6kLGPL-3.0FreeBigBlueButton为在线教学设计的网络会议系统，配备白板、投票和分组讨论室self-hostedweb-basedcollaborativeAlternative to: Zoom, Microsoft TeamsExplore
通信6.3kBSD-3FreeMumble为游戏设计的低延迟 VoIP 应用，支持方位音效self-hostede2e-encrypteddesktopAlternative to: DiscordExplore
通信3.7kGPL-3.0Free+1Delta Chat去中心化聊天应用，通过邮件运作并自动进行端到端加密e2e-encrypteddecentralizedmobile-friendlyAlternative to: WhatsApp, TelegramExplore
通信1.3kGPL-3.0Free+1Linphone基于 SIP 的语音视频通信客户端，用于桌面和移动端的互联网电话cross-platformmobile-friendlydesktopAlternative to: Skype, ZoomExplore
通信1.1kAGPL-3.0Free+1Revolt用户优先的聊天平台，为社区和好友打造，提供服务器、频道和机器人self-hostedrustweb-basedAlternative to: DiscordExplore
通信42.5kGPL-3.0FreemiumDiscourse现代化论坛平台，用于文明的社区讨论，支持实时更新self-hosteddockerweb-basedAlternative to: Slack, DiscordExplore
通信21.5kApache-2.0Freemium+3Zulip有序的团队聊天工具，采用基于话题的串联，将邮件与聊天结合以提升效率self-hostedenterprisedockerAlternative to: Slack, Microsoft TeamsExplore
通信11.5kMITFreeGotify自托管推送通知服务器，提供 REST API 用于收发实时消息self-hostedgolangdockerAlternative to: SlackExplore
通信30.5kotherFreemium+3Mattermost安全的团队消息平台，面向企业提供频道、文件共享和工作流自动化self-hostedenterprisedockerAlternative to: Slack, Microsoft TeamsExplore
通信2.7kGPL-3.0Freemium+2Wire安全协作平台，为团队提供加密消息、视频通话和文件共享e2e-encryptedcross-platformenterpriseAlternative to: Slack, Microsoft TeamsExplore
通信33.0kAGPL-3.0FreemiumCal.com面向个人和企业的排程基础设施，支持日历同步和预约页面self-hostedweb-basedapi-firstAlternative to: ZoomExplore
通信21.5kMITFreemiumChatwoot客户互动平台，提供在线聊天、邮件和社交媒体支持渠道管理self-hostedweb-baseddockerAlternative to: Intercom, ZendeskExplore
通信3.6kMPL-2.0FreeThunderbird功能完备的邮件客户端，跨平台集成日历、联系人和聊天cross-platformdesktopextensibleAlternative to: MailchimpExplore
通信15.6kGPL-3.0FreeMailspring美观快速的桌面邮件客户端，具备统一收件箱、稍后处理和链接跟踪功能electrondesktopcross-platformAlternative to: MailchimpExplore
通信5.8kMITFreePapercups开源网站在线聊天组件，支持实时消息和 Slack 集成self-hostedweb-basedreal-timeAlternative to: IntercomExplore
通信2.9kAGPL-3.0FreeFreeScout轻量级帮助台与共享收件箱方案，用于管理客户邮件会话self-hostedweb-baseddockerAlternative to: Zendesk, IntercomExplore
通信700MPL-2.0FreeBetterbird增强版 Thunderbird 分支，改进了界面、搜索并提供体验优化补丁desktopcross-platformprivacy-focusedAlternative to: MailchimpExplore
通信26.5kAGPL-3.0Free+1Signal私密通讯工具，采用端到端加密，实现安全的文字、语音和视频通信e2e-encryptedprivacy-focusedmobile-friendlyAlternative to: WhatsApp, TelegramExplore
通信5.6kGPL-3.0FreeMailtrain自托管的简报应用，具备自动化、细分和活动跟踪功能self-hosteddockerweb-basedAlternative to: MailchimpExplore
通信18.5kApache-2.0Freentfy简单的基于 HTTP 的推送通知服务，用于向手机和桌面发送提醒self-hostedgolangdockerAlternative to: SlackExplore
通信7.2kAGPL-3.0Free+1SimpleX Chat隐私优先的消息平台，无用户标识符，采用双棘轮端到端加密e2e-encryptedprivacy-focuseddecentralizedAlternative to: WhatsApp, TelegramExplore
通信6.2kGPL-3.0Freemium+2Tuta加密邮件服务，提供端到端加密的邮件、日历和联系人，实现安全通信e2e-encryptedprivacy-focusedweb-basedAlternative to: MailchimpExplore
通信3.0kAGPL-3.0FreeMiroTalk点对点视频通话平台，支持屏幕共享、文件传输，且无需注册self-hostedweb-basedreal-timeAlternative to: Zoom, SkypeExplore
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