That's a definition of "locked down" I can't get behind. _Impossible_ for even the most technical person? That would mean basically no device in all of history

That's a definition of "locked down" I can't get behind. _Impossible_ for even the most technical person? That would mean basically no device in all of history could be considered locked down. A more useful definition would be that a device is locked down when the manufacturer has taken measure to halt users from loading their own software, including their own OS. There might be reason to claim Chromebooks aren't locked down, go flip developer mode on and off you go. As for the iPad case, Apple most definitely does not want you to run your own OS. Older iOS devices often have cracks and ports of Android to them, but that takes considerable effort to defeat Apple's locking down of the device.