Google Hangouts (formely Google Talk) is a great communication app that is one of the few that is available for PC, Mac, Android, IOS, BlackBerry (Talk version only for some BB’s) and possibly others. I find it handy to use on the PC with full keyboard but works very well on other platforms. See the 2 links below.
I have used many im, chat, voip and video apps or web clients starting around 1996 when I lived in Australia and the UK but even after moving back to Canada. Initially as a low cost way to stay in touch with friends and family. Also for free access to US & CDN 1-800 support numbers not available overseas.
Then it became a better way to stay in touch as they started to support video albeit sometimes choppy audio & or video depending on several things. This is a lot better now that internet, computer and device performance has improved greatly.
Some of these were Net2phone, IRC, Messenger (MSN, Windows, Live, etc ..), Skype, Google talk and others.
Google Talk (now Hangouts) was and may still offer free long distance calls inside Canada and US but a cost if outside these 2 or calling international from them.
Find hidden animations in Hangouts: