Slack, one of the world's most popular group messaging apps that is widely used in corporate settings, announced that it rolled out a voice calling feature on Wednesday, enabling its users to not only chat with one another but also call each other.

The upgrade to Slack's services has been one of the most requested upgrades from the app's 2.3 million daily active users and 570,000 paid subscribers. Currently, the upgrade is available to some of the app's users, but is still limited to Slack on desktop on the Chrome browser.

As for those who are using Slack for mobile, as well as those who are wishing for Slack video calls, there is still some waiting that is to be done. Slack, however, promised that other upgrades are coming soon.

With the addition of voice calling and/or conferencing, Slack has managed to become one of the biggest threats to web-based voice calling giants such as Skype and Google Hangouts. Though Slack has integrated with a number of voice calling apps such as Zoom and Bluejeans, having a built-in voice calling function would still better serve the company and its wide user base.

In order to find out if Slack's voice call feature is already available, Team Admins and members must download the app's latest version. Admins simply need to check the Team Settings to see if the voice call feature is already available. If the option is there, the team is ready to start using the feature.

Slack's voice call functions a lot like Skype's voice calls, with its capability to support numerous people interacting in one active call. True to Slack's lighthearted, open style, its voice call interface even includes emojis, in order for those participating in a voice conference to post emojis in real time. Doing so enables the participants of the call to react to whoever is speaking without interfering and cutting someone off.

April Underwood, Slack's v.p. of product, said that the voice call feature is intended for quick conversations between team members. "If I'm DMing someone in Slack and we want to switch to have a quick voice conversation, it addresses that problem," she said.

With video calling in the future and with voice calling already being rolled out, Slack just might be the next big player in the corporate communications world.