TeamViewer is a beginner-friendly, feature-rich remote desktop management tool that boasts exceptional security features, an intuitive user interface, and a great selection of extra screen sharing and conferencing tools.
AnyDesk - AnyDesk is the world's most comfortable remote desktop application. Access all your programs, documents and files from anywhere, without having to entrust your data to a cloud service.
Empathy - Apps/Empathy - GNOME Wiki!
LogMeIn - LogMeIn gives you fast, easy remote access to your PC or Mac from your browser, desktop and mobile...
Pidgin - Pidgin is an easy to use and free chat client used by millions. Connect to AIM, MSN, Yahoo, and more chat networks all at once.
join.me - Instant screen sharing. Instant Aha!
Trillian - Trillian is a decentralized and federated instant messaging platform that lets your whole company send private and group messages, keep tabs on what co-workers are doing, share files, and much more.