iOS (iPhone/iPad) - How to find the version of iOS used on a device
Apple periodically releases updates to the version of iOS used on the iPhone, iPad, and iPod Touch. This document explains how to identify which version of iOS firmware a device is using.
1. Go to the home screen of your iOS device and click on Settings
2. Click on General
3. Click on About
4. Note the number after Version; this is the version of iOS installed on the device. For example, the device pictured is running iOS firmware 4.2.1.