How to make free phone calls, even on your tablet

One of the oldest video calling apps is still one of the best, but both people need to be using Skype for calls to be free. Otherwise, you need to pay to call a landline or mobile number. Some people still use their phones to talk, not just text and surf. If you're one, you can also cut costs when dialing. So long as you're on Wi-Fi -- whether it's your existing wireless network at home or a free Wi-Fi hotspot -- you can take advantage of apps that let you make free "VoIP" calls (Voice over Internet Protocol) on your smartphone or tablet.