Hi I just want to ask from expert here is it possible to downgrade Iphone 12 ios 15.4 to ios 12? Because someone told me it can I just want to make sure.
Downgrade Iphone 12 IOS
Because someone told me it can
That's not the case. It is not possible on a "legal" iPhone.
That's because older versions of iOS are no more signed by Apple, hence cannot be installed.
There is a very limited number of older versions that are signed (today, the oldest is 16.4: https://www.macrumors.com/2023/04/07/apple-stops-signing-ios-16-3-1/)
See technical details here: https://idevicecentral.com/ios-signing-status-results/?deviceID=iPhone13,2