Great App!

If you dont know what is for or how it works dont install it.
Currently this is one of the cheapest way to make calls to europe and asia (at least these are the regions I tried).
you have to buy at least $10 credit but you have certain number of free days, for instance 90 that you can make free calls, and everytime you recharge you increase the number of free days. If you spend hours on the phone they will start charging you the cheapest rate posiible out of the initial credit. If you have regular shorter conversations the credit will last you months!!!
Check out the app for iOS!!
Great app, highly recommend.

gimarizant about VoipRaider