Nymgo is a program designed for Mac users who need to make local and international calls from their computers. This utility provides you with a straightforward interface, allows you to easily make affordable calls to various countries around the world, and lets you import contacts from your default address book app.
The first thing you need to do after installing this application on your Mac is to create a personal account on the homepage of the developer (you need to validate the account by clicking a link sent by the developer). Afterwards, you can log in using the entered credentials and start making calls to your friends and family.
The program offers a simple interface that features a dial pad on the left side of the screen. There's also a world map and an integrated search tool which help you easily locate the country where you need to make the call to.
If you ask me, it should've been a small credit available to test the sound quality by making a short call. That's way, you won't regret acquiring any credit for dialing with Nymgo.
Though, you can find much cheaper solutions for reaching out to your friends and family. There are plenty of VOIP applications that allow you to make international calls without paying any fees. So, it's up to you to decide whether it's worth installing Nymgo on your Mac or not.