said by en102:There are a couple of logical pieces that nobody has mentioned.
1. You can use an old 'dumb phone' (or purchase a gophone, etc). And use it
2. When you want to use data, add standard 'data', and use your PDA phone again.
There is no 'contract' on data, and you can easily swap out phones.
What AT&T has become good at is associating the type of phone you have by IMEI. I think they perfected this process to ensure iPhone 3G users pay $30 instead of $20 for data. If you have the "wrong" data plan they text nag you and automatically add the "correct" data plan.