Cobalt's Correct Answers

Smartphones used to accumulate kb usage when picture/video messaging, but it was changed to not be so starting in December of 2007, whereby the messages just used up your allowance of messages.   If you went with the pay as you go kb plan for your smartphone (assuming your smartphone was released before November of 2008 when the data plan became necessary), you will not accumulate kb usage for sending/receiving picture/video messaging.  You would only generate kb usage when using the internet browser/email functions on the phone, or using any other software that you downloaded on to the phone that required internet access.

The 250 message, $5 text plan does not allow for unlimited mobile to mobile messaging.  The next plan up, the 500 message plan for $10 a month does include unlimited mobile to mobile messaging, though.