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How long does the hinge of a foldable iPhone last? Apple doesn't specify. A homemade folding robot therefore opened and closed the iPhone Duo for four nights – and the result was different than expected.
US journalist Joanna Stern subjected the iPhone Duo to a long-term test for her YouTube review, a test that was missing from previous reviews. While initial reviews consistently praised the hinge, they only described the impression after a few days of use. Stern, however, had the device folded by a machine specially built for this purpose by hardware designer Aaron Cohen. The iPhone Duo will be available in stores in Germany, Austria, and Switzerland starting Friday, October 23.
Key Facts at a Glance
- A homemade folding robot folded and unfolded the iPhone Duo 32,640 times over four nights.
- Afterwards, the hinge was measurably slightly stiffer, but in everyday use it was hardly different than on the first day.
- Apple does not specify how many folds the hinge should withstand.
- Samsung specifies 200,000 folds for the device and 500,000 for the display of earlier models.
- The test was conducted with a single device, with a case and without fully closing the case.
This is how the test went
The machine consists of a servo motor, 3D-printed parts, and a controller that allows adjustment of angle, speed, and pauses. The iPhone Duo is inserted via MagSafe. Stern set an opening angle of approximately 130 degrees at medium speed.
| Parameter | Value |
|---|---|
| Folds per minute | 17 |
| Running time per night | 8 hours |
| Folds per night | 8.160 |
| Length of time | 4 nights |
| Folds overall | 32.640 |
| Opening angle | approximately 130 degrees, not completely closed |
| Device | with case |
Before the test, Cohen used a calibrated force gauge to measure how much force was needed to open the device. The same measurement was repeated after the four nights.
The hinge became tighter
Things didn't look good at first: After the second night, the hinge seemed looser. However, the final measurement showed the opposite – the iPhone Duo required slightly more force to open than before. Nevertheless, Stern noticed no difference in everyday use. Her conclusion:
After 32,000 folds, it felt practically like the first day.
The report doesn't answer whether the crease in the display was more noticeable after the test. In comparison to the Galaxy Z Fold 8, Stern notes that the crease is more clearly visible on the Samsung device, but remains present as a slight indentation on the iPhone Duo. This aligns with Apple's own statement that they want to be judged by the crease.
Apple hasn't given a number, but Samsung has
Apple doesn't specify how many folds the iPhone Duo's hinge is designed to withstand. According to Stern magazine, they only state that it's resistant to wear and tear and meets the high standards expected of an iPhone. Samsung is more specific, but cites different measurements depending on the model.
| Device | Info | Relation |
|---|---|---|
| Galaxy Z Fold 6 | 200,000 folds | Device, according to Samsung |
| Galaxy Z Fold 7 | 500,000 folds | Display, test from Samsung Display (2025) |
| iPhone Duo | not specified | – |
Samsung Display estimates that an average user folds the screen approximately 100 times per day. Based on this figure, the 32,640 folds recorded in the test correspond to about eleven months of use.
A good sign, but not proof
I find the result encouraging, but nothing more. A single device, a homemade machine, and an opening angle where the iPhone is never fully closed – this isn't a lab test and doesn't replace the manufacturer's specifications. However, the fact that the hinge was tighter rather than looser after four nights doesn't suggest premature wear.
Until Apple itself announces a figure, repair remains the expensive residual risk. Apple estimates the replacement of the internal display in Germany at €1,149 without AppleCare, and €99 with AppleCare; there is no separate item for the hinge in the iPhone Duo repair costs.
Is such a long-term test enough to reassure you, or will you wait to buy until Apple provides its own durability rating for the hinge? Let us know in the comments how much confidence you have in the hinge.
