CallMeNow can be intuitively used easily by any user
Have a group chat or group call with unlimited users (video with 6 additional users)
CallMeNow is available for IOS, for Android, for Webbrowsers with Java support and also for MacOS and Windows OS (64bit)
Beside the fact that CallMeNow is nicely designed, it offers an excellent speech quality for VOIP user to user calls (of course it depends on the users internet connection)