how to update ios to a specific version [closed]

Question

During our App test, we need to make sure our App works well on most iOS versions. And is there a way to update iOS version of iPhone to a specific version?

Answer 1

You can upgrade an iPhone to a newer version, but beware, you cannot then change back to a lower version of iOS. i.e. Once a phone is on iOS 5.1, you cannot then change it back to iOS 5.0.

To do the upgrade, you use the Organiser window in XCode. Select the "Devices" tab, and you will see the option to change the iOS version for that device.

Apple recommends (as do I) that you have separate devices for each iOS version you wish to test on. Therefore, one iPhone per version. Then you can easily test your code on all the different versions of iOS.

See the documentation here

Especially this note:

Important The version of iOS you install must be the same as or newer than the version currently installed on the device. Attempting to install an older software image will fail. After a failed installation attempt, you must reinstall the last successfully installed version or a newer version of iOS.

Answer 2

I believe in iTunes you can upload firmware that you've downloaded. I used to use http://www.felixbruns.de/iPod/firmware/ to get the link to the firmware hosted by apple I wanted when I was jailbreaking. When you plug in the device, you should get a screen that allows you to check or install updates, and if you shift-click on it, you can select a file.

Note: I'm doing this from memory from about a year ago, but if I'm not precisely correct, I believe I still have the right idea and path forward.