In flight mode the connection to the network is deactivated, so as not to cause interference with sensitive equipment - eg in a plane or a hospital.
You can still use the calendar, play games etc. Follow these instructions to activate or deactivate flight mode on your Apple iPhone 4.
- Find Settings
- Activate or deactivate
Press the indicator next to Airplane Mode
Depending on the current setting, the function is activated or deactivated
Press the Home key to return to standby mode