I want to have the URL for Hangouts, in order to open it directly, similar to the one used for Google Contact.
That is, I don't want the Hangouts to be a popup to the G+ site. Is such thing available?
ps.
I wan to pin it on my taskbar as a shortcut to application – a feature of Chrome browser.
Best Answer
Short Answer
http://hangouts.google.com
Explanation
When this answer was originally posted, there was not a Google Hangouts standalone app. It was launched in August 2015. On the first days, the 'hangouts.google.com' redirected to 'talkgadget.google.com' but nowadays the redirection was removed.
Other ways to access to Hangouts
Besides the standalone web app, it's possible to access Hangouts from the desktop without going to Gmail or Google+ web sites:
References