OTO is a great application that provides internaional calls from KOREA, JAPAN.

Call originated from the other country will be supported soon.

OTO international call is..
a free international call service with no international call charges
A local call fee from the payment system of the user’s smart phone occurs, and there is no duplicate billing.
-mobile & phone
America,Singapore,China,Canada,Thailand,Puerto rico,Hongkong,Guam,Virgin Islands,Saipan,Alaska,Hawaii,
India,Romania,Macau,Malaysia,Samoa,Brunei,Trinidad and Tobago,Greece,Germany,Belgium,Israel

-phone
Netherlands,Norway,NewZealand,Taiwan,Denmark,Malaysia,Sweden,Switzertland,Spain,Argentina,Ireland,U.K,Austria,Estonia,Israel,Italy,Japan,Czech,Chile,Portugal,Poland,France,Finland,Hungary, Australia,Mexico,Brazil,Iceland,Andorra,Indonesia,Peru,Guadeloupe,Georgia,Lithuania,Monaco,Morocco,Malta,Venezuela,Saudi Arabia,Slovakia,Slovenian,Uzbekistan,Iraq,Colombia,Kazakhstan,Cyprus,Paraguay,Martinique