Under Cellular Data, check the number next to Current Period. If you want to check when the current period for your iPhone data usage tracking began, scroll to the bottom of the screen.

Data can cost you big bucks if you're not paying attention. This article explains how to check data usage directly from an iPhone or Android phone or through a major carrier, such as AT&T, Verizon ...

For these reasons, it’s important to know how to check data usage on your Android device — and to learn how to manage it. We’ll run you through everything you need to know in this quick guide.

Check Your Data Consumption: In the “Data Usage” section, you will see a graph showing your data usage over a specific period. This period typically aligns with your billing cycle.