Aianna

Very strange service with many technical issues. You can try at your own risk.
But be careful, it can drain your phone battery and your money very fast.
May be it is better to use Sipmobile?
Below the description.
Aiannaone Telecommunications is an affordable and easy-to-use broadband telephone and videophone service. Designed with both residential and business customers in mind, AiannaOne allows anyone with broadband (high-speed) Internet access to use their regular phone to make calls to anywhere around the world. AiannaOne subscribers with videophones can make video calls from anywhere Ethernet is offered that is DSL or Cable. All AiannaOne subscribers get worldwide UNLIMITED calling to other AiannaOne subscribers at no extra charge. Calls to non-AiannaOne international numbers (outside the U.S. and Canada) are charged at a very low per minute rate. No contract.
Please note: to make calls you need sign-up to Aiannaone account.
Main features:
Connectivity through WIFI, 3G, EDGE and GPRS
Making and receiving VoIP audio and video calls
Get a second Land Line number for your Mobile
Contacts (phone book)
Loudspeaker
Time, call status logs
Last calls log
Redial
sending and receiving SMS over VoIP