I've talked before about the various definitions of mCommerce, and how no two people seem to have the same understanding of what the term means.
It's hard to define mCommerce. Sometimes it's easier to say what it is not, rather than what it is.
Here's my take - mCommerce is *not* doing eCommerce on a mobile device. eCommerce will always be eCommerce, irrespective of the device you use to do it. A quick rule of thumb - if you're using a browser, you're doing eCommerce. Even if it's the safari browser on your iPhone 4, you're still doing eCommerce. Not mCommerce.