Reports indicate that some iPhone Duo devices are developing cracks along the hinge, affecting the display. These cracks often manifest as a line of bright pixels across the screen. One user reported their device cracked after being opened fewer than 20 times, with no prior visible damage. The cracking occurred audibly as the device was opened, with no obvious cause. Apple replaced the damaged device, suggesting they are investigating these failures. Images of similar cracked displays have also surfaced from demo units in China. While user damage cannot be entirely ruled out for all reported cases, early folding tests by reviewers did not reveal this issue. It remains unclear how widespread the hinge problems are currently. Failures due to normal use are expected to be covered by the one-year warranty. Buyers also have a two-week window for returns if they encounter issues with their new iPhone Duo.