A YouTuber has taken a CT scan of the hinge on the iPhone Duo and uncovered both how it works and what its limitations are.

One of the surprises at the iPhone Duo launch was how it wasn't just built to either be fully open or fully closed. Instead, Apple has built it to offer different functions at many different angles.

According to testing done by HTX Studio on YouTube, iPhone Duo can stay open between 15 degrees and 145 degrees. If it's held below 15 degrees, magnets mean it will snap shut. Similarly, beyond 145 degrees, the screen will snap to fully open.

Apple has already said that its hinge contains almost 100 components. A CT scan of the hinge shows that this is concentrated in six sections, including two at the outer edges that are hinges connected to a central shaft.

Another section is a series of gears that are made so that rotating one side of the device also rotates the other.…