I have a Samsung, using Verizon, and both Samsung and Verizon provide data monitoring apps. The Verizon one even has a meter that shows how much you've used this month on the icon itself.
See if Apple and/or your provider have similar apps.
__________________
_________________
|...............| We live in the nick of times.
| Len 17, Wid 3 |
|_______________| [pics]
|