Apple's first foldable iPhone, expected to be unveiled within days, is reportedly coming off production lines only slowly. Citing supply-chain sources, Japan's Nikkei business daily reports that just "a few hundred" units are being assembled per day. Apple and its suppliers are working to accelerate the ramp, but strict quality standards are holding output down. Earlier reports had already suggested deliveries could slip into October or later — for a September launch, production would normally need to be running at full speed by now.

A supply-chain manager familiar with the situation told Nikkei that "at the initial volume it could be difficult to satisfy market demand." Apple is said to have planned between 9 and 10 million units for the first year — significantly fewer than for standard iPhones. Production is now expected to be scaled up to tens of thousands of units per day to hit those targets.

The problem areas are reportedly the flatness of the display and the durability of the hinge. Nikkei says Apple is demanding a better yield and ordered an additional trial-production round in August, which slowed the process further. Foxconn is again expected to be the main assembler. Commercial production may have been pushed back by months as a result of the extra testing.

The foldable device, which has been circulating under the name iPhone Ultra, is expected to be Apple's most expensive iPhone ever: at least $2,000, and possibly €2,500 or more in Europe. Apple is said to require that devices survive "more extreme conditions" than rivals' foldables — including significantly more folding cycles, so that the typical center crease does not appear too quickly in daily use. For buyers, the practical upshot is likely to be sold-out launch inventory and long waiting times.