Although I have written about many VoIP softwares and some of them work on cell phones, and I am going to introduce more good VoIP in the future, but none of them would let you make free VoIP calls.
However this time I would tell you right now there are really free VoIP calls and it has been tested again and again by others. In order to take advantage of this, you need to live in US or have a US phone number as this free service reads your caller ID before you make any free calls, so, yes, if you live outside of US, you need something like Google voice account, it always show a US local number.
This free VoIP service only let you five (5) minutes each call. It hang up after 5 minutes 30 seconds automatically. You only have to call one of the local access numbers on the homepage of Free phone2phone website, and then you can dial the number you want to over 50 countries for free. Make sure you are calling landline numbers, because you can only call China, Hong Kong, Singapore and India cell phone numbers free of charge.
If you have a long distance plan, or unlimited free calls plan on your local or mobile phone, then this free phone service really works great.
However bear in mind that most US carriers only allow up to 3000 minutes of free calls from landline phones, so yes, you should always use your cell phone.
Why it’s free? Well Free phone2phone earns money when you call their access numbers either from your cell phone or regular landline phone.