Determine your current device software version and check for updates.
INSTRUCTIONS & INFO
From the home screen, tap Settings.
Tap General.
Tap About.
The "Version" number and "Carrier" number information is displayed. Note: For additional information, or to update to the latest software version, please visit http://www.apple.com/iphone/softwareupdate/.
To check for an update, connect the device to a computer and iTunes will let know you if an update is available.