Slack announced this week that a beta product dubbed “Slack Calls” that allows users to make voice calls to one another using its chat software is no longer in invite-only beta. It’s open to everyone and available across platforms including Windows, OS X, iOS and Android.

If you’re unfamiliar with Slack, it’s a fantastic tool for group chats. It’s primarily used in the office space as a “work chat” but has the appeal to attract groups of family and friends, too.

The new “Calls” feature lets any member quickly call another right from the Slack application. I’ve used it several times in beta and found it mostly reliable, as much so as Skype, which is saying a lot. If you want to make group calls, you’ll need to use the premium paid version of Slack, however.

Slack users should find the new call button in the latest software now.