Spacetime

Nowadays, more than 40% of employees spend at least some time working remotely. That's why we built Spacetime – so you can see where your calendar overlaps with everyone on your remote team, without ever leaving Slack.

We've put together a full case study you can see exactly how it works.
http://bit.ly/2PdgU1d

Or - give it a try at https://spacetime.am. We'd love to hear your feedback!