What is a free SMS?

It is a kind of software. After use, send short messages through GPRS under the software interface, and only charge GPRS communication fee, not information fee. GPRS users with monthly subscription use it well, but I suggest LZ not to use it. After using it myself, I found that I often received a lot of spam messages, and I suspected that this software company would transfer the user's number to SP manufacturer. Because the sent SMS must pass through his server and then forward to the SMS center of the operator through him, the software company must know the number of the user. ) it's annoying, after all, there is no such thing as a free lunch.