When you talk about the Internet, it is easy to communicate with other people who use certain messenger service software. But the thing is, the other person on the line should be using it. Some of these programs offer an interface to mobile phones but the whole issue here is cost. When you make calls from two points with the same software, they are free.

In any undertaking, people always want to minimize on cost if not avoid it. Quality may be an issue for some VoIP-using services but they should go with the flow and work on improving it if they want to be the preferred one over the rest.