Slack now integrates with Google Calendar, allowing users to receive reminders in any channel
Google Calendar Reminders Come to Slack — As a user of Slack, you're organized, you're on the ball, and you're well connected to your team. Every once in a while though, something falls through the cracks and you forget a meeting.
Context & Ripple Effects
This 2015 announcement is the earliest data point in a long Slack arc around calendars: the company starts by piping Google Calendar reminders into any Slack channel, then months later Google extends Reminders across its own iOS and Android apps, tied to Inbox, Keep, and Now. The question both moves answer is the same — which surface owns the moment before a meeting.
First-order effects
- Slack users stop relying on Google's own notifications: meeting alerts now land in any channel they choose, making the chat app the delivery point for calendar events.
- Google Calendar gains a distribution surface inside a third-party workplace tool it doesn't control.
Second-order effects
- Calendar-awareness becomes a build-or-buy decision for Slack — three years later it acquires Astro, a startup built specifically to surface important information from emails and calendars, rather than keep integrating around the edge.
- Google responds on its own turf by pushing Reminders deep into its consumer apps, defending its position as the default place where to-dos live.
Third-order effects
- If the pattern holds, chat platforms consolidate the scheduling and task layer around themselves — a direction Slack confirms when it later previews new calendar integrations, responding via email, and universal search as core roadmap items.
The trend: Workplace chat is absorbing the calendar and task-notification layer, forcing both platform owners and point-tool startups to decide whether to integrate, compete, or be acquired.