Tom’s Guide testing found Apple’s first foldable retained significantly more graphics performance than Samsung’s Galaxy Z Fold 8 during a 20-minute benchmark, despite reaching higher exterior temperatures.
Tom’s Guide’s thermal testing suggests that Apple’s iPhone Duo is the stronger foldable for sustained heavy workloads, even though it runs hotter on the outside. In a 20-minute 3DMark Wild Life Extreme Stress Test, the phone delivered a higher stability score than Samsung’s Galaxy Z Fold 8, pointing to better performance retention under prolonged pressure. The result matters for anyone who plans to use a foldable for gaming, video work or other demanding tasks, where heat management can determine whether performance stays smooth or begins to fall away.
The test was carried out in Tom’s Guide’s studio with both phones unfolded, set to their default refresh rates and allowed to cool naturally before benchmarking began. Their displays were then driven through the same synthetic workload while a FLIR thermal camera recorded the rear panels. The two devices behaved very differently. The Galaxy Z Fold 8 developed a concentrated hotspot near the top of the chassis, consistent with the processor area, before heat spread across the back and into part of the screen. By contrast, the iPhone Duo dispersed warmth more evenly across its body, producing a broader heat map rather than a single intense point.
That difference in thermal behaviour did not translate into the cooler phone being the faster one. Tom’s Guide measured the iPhone Duo at 103 degrees on the exterior, compared with about 96 degrees for the Z Fold 8, yet the Apple device retained more of its graphics performance over the full test. Its stability score reached 67.9%, versus 51.4% for Samsung’s foldable. The best loop score also favoured the iPhone Duo at 7,639, ahead of 7,047 for the Z Fold 8, while the lowest score at the end of the run dropped less sharply on Apple’s device. That pattern indicates that a warmer shell can be the by-product of more effective heat transfer away from the chip itself.
Tom’s Guide attributes the difference to the cooling hardware inside the two phones. The iPhone Duo uses a vapour chamber arrangement, while the Galaxy Z Fold 8 relies on more basic thermal materials. In practice, that appears to let the Apple handset pull heat away from the processor more efficiently and spread it through the frame, whereas Samsung’s device keeps more of that heat concentrated near the top. Internal sensor data recorded during the test reinforced that picture: the Z Fold 8’s core temperature rose from 95F to 113F, suggesting the chip was under greater thermal stress despite the cooler exterior reading.
The broader context is important. The iPhone Duo is Apple’s first foldable and has already been described by reviewers as a premium but imperfect debut, with concerns ranging from price and weight to limited third-party app optimisation and the lack of a telephoto camera. Other reporting from Tom’s Guide says it also carries a 4,883mAh battery, slightly larger than the Z Fold 8’s 4,800mAh cell, while tech reviews have praised its performance, display quality and battery life. Against that backdrop, the thermal result strengthens the case for the Duo as the better option for sustained gaming and other long-duration tasks, even if its outer surfaces feel hotter in the hand.
Disclaimer: This content is intended for informational purposes only. Readers are advised to exercise their own judgement, conduct due diligence, or consult a qualified expert before acting on any information provided.
