Skype

Skype, originally a peer-to-peer voice and video communication platform, has since transitioned to a more comprehensive communication and collaboration platform owned by Microsoft. While they offer advertising solutions, this is not their primary focus. Skype`s advertising products cater to businesses looking to connect with their customers through various channels within the platform, including targeted messaging, video advertising, and sponsored placements. These ads can reach users across desktop, mobile, and web versions of Skype.

Website: https://www.skype.com