Kakao Talk, the mobile messaging company that’s undergoing a $3 billion merger in its native Korea, is taking a leaf out of the Skype playbook after it introduced free voice calls to its Windows app. The company added calls to its mobile apps back in 2012.

Voice calls are supported in one-on-one conversations, and also in groups with up to five participants. In addition to free calling, Kakao Talk has also rolled out a design with new fonts, which lets users customize their chatrooms with themes, as they can on the mobile apps.

The company’s Windows app launched in June 2013, with a Mac version following in May of this year. Kakao Talk has 150 million registered users worldwide — together, the two desktop apps have collectively gathered 30 million downloads, the company says. There’s no word on when free calls will come to the Mac app, though.

Kakao Talk for PC