Anyone can join.

A new update to Skype for Windows, OS X and browser makes it possible to join a Skype call even if you do not have an account, a feature that was in beta in March.

Users who are already in conversation, generating a code they can send to others who wish to participate but do not have Skype installed.

Upon opening the link, the user can join the call via the browser or mobile device.

We have to wait
Currently, the function only available to users in the US and UK, but Microsoft plans to roll out the service to additional markets in the coming weeks.

In addition, iOS and Android apps updated to support the new feature, but surprisingly enough is not Windows 10 or Windows Mobile Phone mentioned.