Sure signal app for Vodafone?

[giveherlong]

Does anyone know if there is an app for Vodafone similar to o2's TU GO  which works like sure signal enabling you to use your phone to make calls and receive calls SMS etc over the internet when you have no network coverage?

[Tubberman]

Can't you use Skype, viber or whatsapp?

[giveherlong]

I do use viber but need the odinary phone for work for incoming calls