CNET's hardware testing lab says its custom-built machine has opened and closed Apple's first foldable phone, the iPhone Duo, more than 200,000 times without turning up any indication of damage, according to CNET Japan. The outlet, which bought its test unit for roughly 360,000 yen, has been running the device through repeated fold cycles for a little over a week at its lab in Louisville, Kentucky. The machine, which the team calls "Fold-a-Phone," has one job: keep folding the phone until something gives.
The test is being run by the outlet's head of hardware and software testing, who says the team has been checking the unit at regular intervals and has so far found no signs of wear. CNET Japan reports that the exercise is meant to answer questions readers have raised about how well the hinge holds up and whether the phone is likely to fail or crack.
Why it matters
Apple's arrival is a significant moment for foldable phones. Samsung released the original Galaxy Fold in the United States in September 2019, which means Apple is entering the category about seven years later. Motorola and other manufacturers have experimented with foldables in various shapes and sizes for years, including a triple-folding design CNET tried in 2019.
CNET's mobile specialists have argued that the iPhone Duo's launch will raise the profile of foldables generally, since the category has so far remained more of a vision of future devices than a mainstream product. With Apple now competing against existing foldables, the field is effectively complete — which is part of why the outlet says the durability data matters.
Apple has not disclosed how many folds the iPhone Duo is rated to survive. CNET Japan says that gap makes independent testing valuable for anyone trying to understand both Apple's first foldable and its rivals.
How the rig works
The outlet designed and built its own apparatus rather than buying one, and spent months on the testing method and the machine in anticipation of a foldable iPhone. The same rig is also being used on Samsung's Galaxy Z Fold 8.
The setup is meant to approximate ordinary use rather than stress the phone at maximum speed. Few people snap a phone open and shut all day; typically a user opens it at a natural pace, spends a few minutes watching video, reading a page or using an app, then closes it and puts it away — dozens of times a day.
CNET settled on a cycle of about four seconds: one second to open, one second held open, one second to close, and one second held shut. That counts as a single fold, and the rig runs at roughly 900 cycles an hour until the hinge or a display fails. The team says it chose that pace to avoid technical problems while still accumulating results quickly.
The machine is built from off-the-shelf components to keep design and construction simple. Two arms do the folding, each engineered to apply firm but smooth force. Industrial stepper motors drive the arms, with software on a connected computer governing the motion step by step. Proximity sensors act as a safety check: if any one of them fails to confirm an arm is in the right position, the rig stops immediately.
The team also tracks the motors' power draw to see whether the phone becomes easier or harder to open as testing proceeds, and has set up cameras to capture photos and video from several angles. Status data is exported from the computer at intervals for analysis.
Each phone sits on a mount printed on a Prusa Core One 3D printer, which CNET's lab testing previously ranked at the top of its category. The mount is printed to the exact dimensions of the individual device, attached to the phone with strong double-sided tape, and screwed onto the rig.
What the numbers mean
Most current foldables are said to withstand somewhere between 200,000 and 500,000 folds. CNET says it needed a sturdy, flexible rig that could handle both book-style and clamshell designs regardless of size, dimensions or hinge orientation. Triple-folding devices were left out because their mechanisms raise different problems.
The outlet is streaming the test on YouTube on weekdays from 1pm to 5pm Eastern time, so viewers can watch the rig work in real time. It says it will keep publishing progress updates and comparisons as the internal data builds up, alongside its written review of the device by senior technology reporter Abrar Al-Heeti.
For now, the phone keeps folding. What to watch is whether the hinge or either display shows the first sign of failure, and how the iPhone Duo's cycle count compares with the Galaxy Z Fold 8 on the same machine.
