10-09-2012 15:03 - edited 10-09-2012 15:05
It supports all three of those apps.
Skype - http://www.windowsphone.com/en-GB/apps/c3f8e570-68
If you intend to video chat be aware that the Lumia 710 does not have a front camera. You would need a Lumia 900 for that feature.
I think it's fair to point out that all of those apps are basically crippled in WP7 due to the way WP7 handles multitasking; you can open Skype, WhatsApp and Viper, but when you open another app, they close down meaning you are unavailable to the outside world through those apps.
I would wait for a WP8 device. True multitasking means the apps continue running in the background.