What are some alternatives?
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.
Diaspora - The online social world where you are in control.
Jitsi - Open-source video calling and chat platform.
Facebook - Connect with friends, family and other people you know. Share photos and videos, send messages and get updates.
Skype - Stay in touch with your family and friends for free on Skype. Download Skype today to chat and call on desktop and mobile.
Twitter - Connect with your friends and other fascinating people. Get in-the-moment updates on the things that interest you. And watch events unfold, in real time, from every angle.