Net Counter is a great application to keep track of your daily, weekly, monthly, or whenever you decide to reset it data meter. The program is free on the Android Market and is useful if you want to keep track of how much data you consume over a billing cycle. Most data plans have a soft 5GB limit, which means you may go over a couple times but too many and you may get a call from your service provider. At&t has recently changed the way that they bill for data and offer a 250MB plan and a 2GB plan. This may be the best option for you though if you use less data. Net Counter is also capable of showing how much data you are using through your WiFi connection.