Introduced back in October 2010, Skype says its Android application, which received video calling support about a year ago, has been downloaded over 70m times from the Google Play store to date.
However, there isn't yet a way to call other WhatsApp users who don't also have video calling support.
The iOS app was also updated just last week, but video calling support was not included at that time.
After registering, Skype says it will send you an email after it has set up group video calling support on your mobile device.
Today, apps like Houseparty, Instagram, and Snapchat, among others, cater to this audience with group video calling support of their own.
For those on a version of WhatsApp which includes video calling support, you're able to tap the call button or tap on a contact card to kick off a video call.
Just in time for the launch of the EVO 4G (and its front-facing camera) next week, Fring has tossed 2-way video calling support into their free Android app.
"Voice and video calls are supported in wired environments".
However, video calling is supported only on an up-to-date Lync 2013 client on Android, iOS or Windows and on Skype for Windows desktop.
Landscape mode is also now supported during video calls, as is support for switching between front and back cameras.
Services such as file transfer are supported, although video calling is only supported between Gizmo users, and not with users on other services.
