iOS VPN App
Apple has stopped signing iOS 15.1 for the iPhone 12 and 13, preventing users from being able to downgrade or restore to that firmware version.
Those interested in jailbreaking are typically advised to stay on the lowest firmware possible. The checkra1n jailbreak makes it possible to jailbreak most devices between the iPhone 5s and iPhone X on any firmware version above iOS 12.3; however, an iOS 15 update has yet to be released. The unc0ver jailbreak and Taurine jailbreak support all devices running iOS 14 – 14.3. Unc0ver has also been updated with the Fugu14 untether which supports iOS 14.4 – iOS 14.5.1.