Slack News Feed - Get the top posts from every Slack chat you're in.
Tettra - Tettra is a company wiki that helps teams manage and share organizational knowledge.
Slack-News - Read news from multiple sources within Slack by just typing
Slinky - Your slack links — organized!
Slack Platform News - News and updates from the Slack Platform direct to your team
Obie.ai - Access knowledge quicker without leaving Slack