Secure, self-hostable team messaging.
Self-hosted apps listings
Open-source communication platform.
Self-hosted file sync and collaboration suite.
Self-hosted photo and video backup.
Free media server for your own collection.
Open-source survey and experience management.
Open-source help desk.
Cards

Mattermost
mattermost.com
Mattermost
Secure, self-hostable team messaging.

Rocket.Chat
rocket.chat
Rocket.Chat
Open-source communication platform.
Nextcloud
nextcloud.com
Nextcloud
Self-hosted file sync and collaboration suite.
Immich
immich.app
Immich
Self-hosted photo and video backup.
Jellyfin
jellyfin.org
Jellyfin
Free media server for your own collection.

Formbricks
formbricks.com
Formbricks
Open-source survey and experience management.
Zammad
zammad.org
Zammad
Open-source help desk.