How to Install iPhone Software Updates Without Connecting to iTunes
Upgrading to the latest version of the iOS used to mean that you had to be in front of your computer, had to connect your iOS device to it, download the update to your computer and then install the update via syncing. But if you have iOS 5 or higher, that's not true anymore. Now you can install iPhone software updates wirelessly. .
Difficulty: Easy
Time Required: A few minutes
Begin by making sure you're connected to a Wi-Fi network. While you'd be able to download an update over 3G/4G, the updates are so big that you'll be waiting a really long time (also, you'll eat up a ton of your monthly wireless data), so Wi-Fi is much easier here. You should also make sure you've got plenty of battery life. The download and installation process can take some time, so if you've got less then 50% battery, you may want to plug in to a power source.
Once you've done this, tap the Settings icon on your home screen.
Scroll down to General and tap on it.
Tap on the Software Update menu. Your device will check to see whether there's an update. If there is, it will report what it is and what it adds. Tap the Download and Install button at the bottom of the screen to begin installing the iPhone software update.
You'll be asked whether you want to download over Wi-Fi (you do) and reminded to connect to a power source. Tap OK. When the Terms screen appears, tap the Agree button in the bottom right.
The download will then begin. You'll see a blue progress bar moving across the screen. When the download is complete, a window will pop up asking whether you want to install the update now or later. To install now, tap Install.
Your device will now begin installing the update. The screen will turn black with an Apple logo and another progress bar will show the installation's progress.
When the iPhone software update has finished installing, your iPhone will restart and you'll be ready to use it with the freshly installed new OS.
Tips:
If something goes wrong with the installation, you have two options for fixing things: Recovery Mode or (if things go really bad) DFU Mode.
If you'd prefer to update in the traditional way, check out this article.
Your iPhone will notify you when there's an update even if you don't check for it. If you see a little red #1 icon on the Settings app, that means there's an iOS update available.