Chaskiq

Communications platform that puts data protection first (alternative to Gitter.im or Slack).

Notification infrastructure for developers.

Platform for secure collaboration across the entire software development lifecycle, can be integrated with Gitlab (alternative to Slack).

A modern CRM offering the flexibility of open source, advanced features, and a sleek design.

Customer communication platform (alternative to Intercom & Zendesk).

Push notifications to phone or desktop using HTTP PUT/POST, with Android app, CLI and web app, similar to Pushover and Gotify.

Zulip is a powerful, open source group chat application.

Personal relationship manager, and a new kind of CRM to organize interactions with your friends and family.

CRM solution for SMEs and Enterprises for complete customer lifecycle management.

Apprise allows you to send a notification to almost all of the most popular notification services available to us today such as: Telegram, Discord, Slack, Amazon SNS, Gotify, etc.

Notification server with Android and CLI clients (alternative to PushBullet).

Instant messaging platform. Backend in Go. Clients: Swift iOS, Java Android, JS webapp, scriptable command line; chatbots.