Is there a way to determine when an iOS upgrade was installed?

Is there any way within iOS, or via iTunes on a computer, to see the date when a particular iOS upgrade was installed on my device (iPhone/iPad)? Not the date the upgrade was released, but the date that it was actually installed.

Solution 1:

If you have updated iOS through iTunes, you can look in your iTunes data folder, on a Windows machine that will be:

C:\Users\[username]\AppData\Roaming\Apple Computer\iTunes\iPhone Software Updates\

Then check out the timestamp on the iPhone..._Restore.ipsw file. That will be the date you upgraded (or downloaded) our latest iOS update.

If you updated it directly on the device, I don't think it is possible to retrieve its date.