mike143 wrote:They can tell you have a smartphone whether or not you enable data. I think the only way around it would to be to clone a dumb phone to a smartphone but that would be illegal in the US.
They can only tell if the phone is within their IMEI database. This only works on GSM network since on CDMA like Verizon, you have to activate your phone. If you purchase a phone for example from another country,the IMEI isn't going to in the network's database and so they can't figure out your phone is a smartphone. If you purchase a phone that is not available on their network, it may work, too but is more of a crap shoot.
Alternately, you can use a prepaid plan. My Android phone is currently on a Tmobile prepaid plan and it doesn't charge me for data plan because my prepaid plan doesn't support data. Tmobile will tell you that this is not a support configuration meaning that they won't support you if you can't update, but update over wifi always work just fine. Certain Tmobile network feature also doesn't work,but frankly I don't use them.
One problem is without a dataplan, you can't get any MMS.