With the recent changes to AT&T's data plans and the introduction of Apple's new iPad with LTE, users should start taking steps to monitor their data usage more carefully on their devices to avoid surprises when the bill comes. K.T. Bradford over at GottaBeMobile.com wrote a great article about a nice app that I have actually been talking about since I got my iPad. Data Usage is an inexpensive iOS app that will monitor your 3G/4G and WiFi data usage and let you know if/when you're getting close to your data cap. Check out her article.