iOS is the operating system software installed on your iPhone. To find out which version you have: Tap Settings, Tap General, Tap About, and view the version number.
Activating or deactivating data connections on my mobile phone
If you want to avoid using data, you need to deactivate data connections on your mobile phone. Once done, you can only make voice calls, send SMS and use applications that don't require an internet connection.
Tap Settings.
Tap General.
Tap Network.
Tap the indicator next to Cellular Data. Depending on the current setting, the function is turned on or off.
