This icon in the notification panel informs that a software update is available. Touch and slide down to show the update in the notification center. You can now launch the update process and follow the instructions in the phone display.
You can also check manually for available software updates, please follow the steps below:
- Press the Home button then the Menu button , and touch Settings
- Scroll down to About Phone and touch to open it
- Select Software update
- Touch OK to check for new software updates