Skype announced that it will be display new ad units within the skype calling window of users who do not have Skype Credit or subscriptions when they’re making 1:1 Skype-to-Skype audio calls using Skype for Windows os.
Source
Skype announced that it will be display new ad units within the skype calling window of users who do not have Skype Credit or subscriptions when they’re making 1:1 Skype-to-Skype audio calls using Skype for Windows os.
Source