Android 4.0 Ice Cream Sandwich has added a key feature for those who are on a capped mobile data plan with their wireless carrier.
ICS gives users the ability to monitor the amount of mobile data being used on their device, and in some cases, automatically turn off mobile data.
Monitoring your mobile data usage on an Android 4.0 device is easy. Here's where to start.
You can access the Data Usage settings screen by opening the Settings app, and then selecting Data Usage. Once you have navigated to the Data Usage screen, you will see something similar to the screen above.
The orange bar on the graph represents a data level at which you will receive a warning. You can adjust the warning level by sliding the orange bar up or down.
You can set the date range for the mobile data measurement to reset itself, matching it to the billing cycle of your wireless carrier. If you want to set a data limit, it's as simple as checking a box.
Once you have checked the box to set a mobile data limit you will then see a red line going across your mobile data graph. By moving the line up or down, you set a mobile data limit for your device to automatically turn off mobile data once the set level is reached.
You can also view your trending usage on the graph, indicated by the dotted blue line going across the graph.
If you are concerned about which apps or tasks are using the most mobile data, you can find an app list, complete with breakdown of mobile data usage by app.
Tapping on an app will present you with a mobile data usage chart for that particular app.
Here you can view a graph of how much mobile data was used, and when. Also, you will be able to see how much mobile data was being used in the background, and how much mobile data was being used while you were actively using the app in the foreground.
To restrict any app from using mobile data in the background, scroll to the bottom and check the box titled "Restrict background data." The app in question will still use background data, but only when your device is connected to a Wi-Fi network.
If you feel more comfortable with not allowing any background mobile data to be used, you can restrict it by tapping on the menu icon on the main Data Usage screen and checking the Restrict background data box.
If you also wanted to view how much data your device is using on a Wi-Fi network, you are able to by simply checking the Show Wi-Fi usage box in the menu.
Keep in mind (as you will be reminded several times by your device), the data figures shown to you on your device can, and more than likely will, vary from the data usage your carrier reports on your monthly statement. To be on the safe side, it's a good idea to set lower warning levels and limits than what your true data limit is in the event your carrier is reporting higher than what your device is.