The app shows a regular dial pad from which to make calls, you can choose a number from call history or you can use your contact list.
The App uses Wi-Fi this means that when and where you travel and have access to Wi-Fi you can make unlimited calls.
The app also gives you the option to make calls using 3G/4G Data or GSM in your own country so you can use your free data/minutes bundle. GSM only available in Canada, USA, UK.
Easy to install and to use.