Following the launch of Apple's first foldable phone, the iPhone Duo, some users reported issues including inner screen cracking and bright lines. Apple CEO John Ternus said the proportion of iPhone Duo units returned due to display problems is extremely small, and the company is replacing affected users' devices with brand-new ones. Supply of the model is also tight. Ternus said supply remains constrained and that Apple is steadily ramping up production capacity to deliver as soon as possible, though he could not yet give a clear timeline for when supply and demand will come into balance. Apple's China website shows that the estimated shipping time for the model has slipped to late January 2027.