Some iPhone Duo owners say Apple’s $1,999 foldable cracked within hours of unboxing—and a possible explanation has emerged

Apple’s first foldable iPhone was supposed to be a statement piece for John Ternus, and instead it has started shipping with a headache. Four days after the iPhone Duo reached customers, Apple began replacing units whose inner screens cracked along the fold, with some buyers saying the damage showed up within hours of opening the box.

The phone went on sale on Oct. 23 for $1,999, after preorders sold out in minutes on Oct. 16. Early reviews were largely upbeat, so the reports of broken displays landed hard. Apple confirmed to CNBC on Monday that it was aware of an issue affecting the inner display on a small number of units and told affected customers to go through AppleCare for a replacement. The stock did not love the news, either: Apple fell 1.1% to $343.91 on Monday and slipped again in premarket trading Tuesday even as the broader tech sector was up.

What buyers are showing online is fairly specific. Photos on Reddit and MacRumors show cracks running down the center line of the hinge, often with a bright horizontal band of stuck white pixels. Tom’s Guide reported one case with a white line on the right side of the display, and an owner in Australia said his phone broke after about six hours and fewer than 20 openings. The total number of complaints is still fuzzy. Bloomberg said the count was growing, 9to5Mac had tallied about 10 unique cases by Sunday, and MacRumors noted that some circulating images appear to be AI-generated.

The best clue so far comes from iFixit’s teardown. Using CT scans, teardown footage and Apple patent material, it mapped the hinge and compared that model with the failure points. The damage appears to cluster just below where a display cable crosses under the screen near a central support bar, Reuters reported. That points to a few possibilities: the support bar may not be fully retracting, pressure may be building in the wrong place, a particle may be getting trapped, or there may be a manufacturing defect.

Apple has not said what is causing the cracking, and it has not announced a recall. The company says most units are unaffected and that the problem tends to show up soon after purchase. Owners do not need AppleCare+ for a replacement, but once warranty coverage ends the economics get ugly fast: Apple lists an inner-screen repair at $999. For now, early buyers are covered, and Apple’s first foldable is getting the classic foldable treatment, which is to say: admiration on one side, and a very expensive weak spot on the other.