Now you can monitor the data usage on your iPhone 4 with realtime reports of both Cellular (3G – EDGE – GPRS) and WiFi .
Set and forget about data quota and billing cycle after you feed the information . Data Usage App will monitor and notify you when you hit your data limits on a daily weekly and monthly basis . Data Usage app works in the background keeping an eye on all you data usage and shows the percentage of data used and data left in a well presented graphical interface as shown in the sample above .
Conclusion : Data Usage is great for those who run the risk of exceeding their data limit. This is a great buy available for $0.99 in AppStore . Link .
Also Read Data Counter jailbreak Apps .