Quick upgrade of ipad iOS 8 official version

There are three ways to upgrade iOS 8 for ipad: whether to update ota or not, whether to update online in itunes, and whether to update the system files after downloading the system files in itunes.

Method 1. OTA update
 
On the main interface of your ipad, click "settings"> "general"> "software update". Here we can see that ios8 is updated before we can click Update iOS8.
 
Method 2: use iTunes to update devices
After downloading and installing iTunes on your computer, connect your iOS device to your computer. Open iTunes, go to "version" in "summary", and select "Check for Updates". Then, the iOS 8 firmware will be downloaded, and install it.
 
Method 3: manually download the iOS 8 firmware and use iTunes to update it

Connect the ipad to your computer, click iTunes, hold down Shift, and click "restore". Select the corresponding version of iOS 8 firmware for restoration.

Reminder: If you want to upgrade ios8 to ota, you must see a push on your mobile phone. You can upgrade the ios8 directly on your computer without a notification on your mobile phone.