Make internet calls via mobile app, desktop app, or mobile SIM card.
The desktop app and mobile phone app are similar to using Skype. The SIM card lets you use Tru as your mobile phone carrier. The SIM would be a good option if you were traveling to many countries, or making phone calls to many countries. Tru describe themselves as a global mobile network. You can set the mobile app to use your normal phone dial pad, instead of having to type phone numbers into the app.
Whether you use the desktop app, mobile phone app or Tru SIM card, the person you call sees your mobile phone number in their caller ID.