Business Insider
I'm not saying you've been missing out, as regular phone calls are fine, but I'm here to tell you there's something better that you've probably had for while without even realizing it - and they're free to use.
Of course, these apps use up a bit of your data, but you'd need to log some serious minutes when you're off WiFi to make any impact on your data usage. They're also perfect for international voice calls, too, as they're essentially free.
Now, these apps aren't perfect, as whoever you're calling needs the same app. That's why I've chosen popular apps that you and your circle are more likely to have.
Check them out: