sim usa VoIP is a VoIP app that allow you to place phone calls from anywhere in the world to more than 60 countries.
You just need an internet access and you can call using cellular service (3G minimum) or Wifi.
The app doesn’t require a sim card to be used. However you need a personal phone number to confirm your identity as it will be used as the Caller ID.
The advantage of the app is that you can keep your personal phone number as a caller ID anywhere in the world.