I have never owned a smartphone before, and am starting out with the 2GB data plan. If I decide that is not enough, or is too much, will I be able to change the plan as I wish, or will I need to stick with it for the full 2 years of the contract?
Also, what about texting — can I add or remove texting from the plan as I desire, or am I stuck with my decision for the full period of the contract?
You're required to have a data plan but you can switch between the different data plans every month if you so wish.
The text message, there are only two options - pay per use or unlimited (either per line or for the whole family). Unfortunately, AT&T has gotten rid of tiered messaging packages. You can switch any time you want.