The firmware that drives an iPhone is refreshed during the "flashing" procedure. Installing a more recent version of the iPhone's operating system is required to accomplish this. Newer versions frequently comes with improved compatibility with new softwares as well as new features . You can do this by launching the Apple iTunes device management application while your iPhone is connected to your computer.
Connect your iPhone to your computer in Step 1.
Open iTunes in Step 2.
Step 3
Select your iPhone by clicking its name.
Step 4
Click "Check for Updates". An indicator that there are any firmware upgrades available for your iPhone will show up on screen. You won't be able to flash your iPhone at this time if there are no upgrades available.
Once the device has been flashed, all of your personal files and data will be synchronized back to it.