title: How can I install an unsigned iOS version on an iPhone?
body: <p>I'm using several devices using older iOS versions to test my apps on actual hardware during development (some features that use the camera or certain Core Image APIs don't work on the simulator). My last app will drop support for iOS 11 soon, and so I'd like to upgrade an iPhone SE that runs iOS 11 to iOS 13.</p>
  <p>The IPSW files can be downloaded from websites like <a href="https://ipsw.me/" rel="nofollow noreferrer">ipsw.me</a>, but apparently there is no official way to install such an upgrade, as Apple no longer signs these firmwares. Is there a way to bypass this limitation?</p>