Download Meter for Wi-Fi/ 3G/ EDGE/ GPRS is a great idea. It lets you conveniently track your data usage -- which is important now that AT&T no longer offers unlimited data. I've never found it that convenient to access my usage on the iPad, and it takes forever to get the info over my Edge connection. This app simply tracks it at the level of your device, so you don't need to long into your AT&T account. It has features such as meters that give you a sense for your usage at a glance. Very useful app, with quite a few good reviews. It even lets you add your own counters to, for example, track usage by a particular app.