You can limit your data usage by turning off mobile data. You'll then not be able to access the internet using the mobile network. You can still use Wi-Fi even though mobile data is turned off.
Step 1 of 5
Press Settings.
Step 2 of 5
Press Mobile Service.
Step 3 of 5
Press the indicator next to "Mobile Data" to turn the function on or off.
Step 4 of 5
Press the indicators next to the required applications to turn the function on or off.
Step 5 of 5
Slide your finger upwards starting from the bottom of the screen to return to the home screen.