Mobile data is always a concern for Android and iPhone users. Phone service isn't cheap, and with HD video and so much more always available to stream in your pocket, it's easy to go way over your data limit.

Android apps that help you use less data when browsing the Web can help, but there are more ways to make sure you don't ever cross the threshold into extra charges.

To make your Android phone warn you when you approach your data limit, head to Settings > Data usage. Here you'll see your current data usage in a graph -- see the line that has a number next to it? Drag that wherever you'd like to set a monthly warning -- 75% of your total is probably a good number.

To make sure this is being measured correctly, check that your billing cycle is accurate right above the graph. Tap the dropdown box and choose Change cycle… to define your start and end dates. Note that your phone's measuring is not official and may differ from your carrier's records.

This tool is great for giving you an estimate, but do plan for some wiggle room just in case.

If you'd like, you can also enable the Set cellular data limit option here and define a threshold at which your phone will block all data connections. This is a great safety net, but it does mean you won't be able to use any data in the background, so be careful when setting it.

Remember that you can play games that don't require a connection if you have to go a few days without data at the end of the month! Check out how you can block any app from using your data if you need to keep an eye on just a few.

Do you use these data warning and blocking features? Share your tips for managing data usage below!

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