I think part of the reason was also to put messages on data. when the iphone came out you could get unlimited data from att, but I think you still might end up

I think part of the reason was also to put messages on data. when the iphone came out you could get unlimited data from att, but I think you still might end up with a plan with finite text messages. Being able to text over wifi or 3g would save you from running up sms. blackberry had something similar too.