@GeneralBattuta: If the whole movie is a dream, then the concept of "dream logic" is created by the dreamer and isn't a constant. You could have four, five, 100, 1 million levels and have it be stable if that's what the dreamer believes.

@thnikkamax: I've heard the theory that the handsets were tested thoroughly, but failed to do so past Apple's rigorous "clean room" conditions. When the phone is taken out into the real world, where we have dirty, sweaty hands, the performance changes.