If you're on a limited data allowance, it's important to keep track of the activities and apps that usually send and receive data, such as browsing the web, syncing online accounts, and sending email or sharing status updates. To help you save on data usage, connect to a Wi-Fi network whenever possible and set your online accounts and emails to sync less frequently.

NOTE: If you connect your phone to another portable Wi-Fi hotspot, tap the three-dot menu, then Mobile hotspots to restrict background data from downloading, and prevent additional data fees.

1. Navigate to Settings > Data usage.
2. Select the tab that displays your mobile operator.
3. Select Set mobile data limit to automatically disable your data connection when you reach the set limit.
4. Drag the upper LIMIT line to set your monthly data limit.
5. Drag the lower ALERT line to set an alert before you reach your monthly data limit.
6. Drag the vertical line markers to see how much data you've used during a particular time interval.
   
   NOTE: Your actual data usage may differ and may be higher than the data usage measured by your phone. Contact your network provider for further assistance.

You can also monitor the data use of individual apps. Follow these steps:

1. Navigate to Settings > Data usage.
2. Drag the vertical line markers to see how much data you've used during a particular time interval.
3. Scroll down the screen to see a list of apps and their data usage info.
4. Tap an app to see more details.