what iphone apps allow me to me free calls oversea without internet connection?

[steepladybug665]

hi im goin oversea with my partner, is there any iphone apps that allows me to make free calls between two iphone without internet connection?

i have chk viber and wats app need internet connection in order to make Free calls.
Thanks

[Andrew]

Without an Internet connection you'll be forced to use your carrier's network, and thus be charged your carrier's fees. Apps will be useless unless you can gain root access to your phone and find an application that takes advantage of your carrier's cellular towers to make free calls which would be illegal.