They probably could build a version of the OS that worked only for single devices. In the latest court case about San Bernadino, that&#x27;s what the FBI is asking for. There&#x27;s a unique device id, as I understand it, that the OS could detect. I believe that Apple is opposing it on principle, and out of concern of the precedent that it would set. Once it&#x27;s been done once, the fact that it&#x27;s been done will significantly lower the bar for it to be done in other circumstances.