title: Installing a lower IOS version than the latest one to a device
body: <p>I know that it is possible to install lower versions of IOS to jailbroken devices over various tools by creating custom firmware.The problem is we have some test devices in the company and we want to have one device eactly with IOS 4.3. It will not be downgrade since the device itself has IOs 4.2.1 installed.Is there a documented way to active it and the most importantly where can i find older IOS versions?</p>