Updating ipod touch
It is advisable to connect your device directly via Wi-Fi to avoid data downloading charges over the 3G/4G connection of your smartphone.
After connecting the device via Wi-Fi, launch the Settings app select General tab and then tap on Software Update.
Step 1: Connect your i OS device to computer via USB cable.
Step 3: Click on "Check for Update" without pressing any keys.The list (at least for the i Pod touch) looks like it is mostly bug fixes and stability improvements, but we're still searching for a full list of all the changes.You can upgrade your phone or i Pod's firmware by selecting, "check for updates" in i Tunes.Let i OS automatically search and identify the latest available update for your device and once the update is listed, just hit the Download button.Wait until the download completes and then tap Install button to apply the new update.NOTE: Jailbreakers are advised to follow the i Tunes method as OTA updates have known issues with jailbroken i OS devices.