Communication & Collaboration

Free alternative to: Paid private messaging services

What it does: Send encrypted messages, share files, and make voice or video calls. Desktop use requires linking to Signal on your phone.

Platforms: Windows · macOS · Linux · Android · iOS 

Free alternative to: Zoom / Microsoft Teams, for video meetings

What it does: Hold browser-based video meetings with screen sharing, chat, and meeting links. Use the free public service or host your own installation.

Platforms: Web browser · Android · iOS 

Free alternative to: TeamSpeak’s paid server hosting, for group voice chat

What it does: Provide low-latency voice chat for gaming, communities, and teams using a server you host or join.

Platforms: Windows · macOS · Linux 

Free alternative to: Dropbox / Google Workspace, for file sharing and collaboration

What it does: Store, synchronize, and share files through your own server, with optional calendar, communication, and collaboration apps.

Platforms: Web browser · Desktop and mobile clients · Self-hosted server 

Free alternative to: Slack / Microsoft Teams, for team messaging

What it does: Organize team conversations into channels and topics, with searchable history and file sharing. The optional hosted mobile notification service has free-use limits.

Platforms: Web · Windows · macOS · Linux · Android · iOS 

Free alternative to: Google Workspace, for collaborative text editing

What it does: Let multiple people edit the same document simultaneously, with author colors and revision history.

Platforms: Web browser · Windows, macOS, or Linux server installation