Here’s Why You Should Pay Attention to the IPhone 18 Pro’s “vapor Chambers.”
During Apple’s major hardware unveiling on Wednesday, the company emphasized the vapor chamber technology in the new iPhone 18 Pro and Pro Max . The simple explanation is that these new vapor chambers can improve performance and reduce heat generation. But how exactly? And what does this mean for the phones you’re planning to buy?
How do steam chambers work?
In its simplest form, vapor chambers work similarly to liquid cooling in other electronic systems, such as some desktop PCs or server racks. The goal is to draw heat away from the processor, keeping it cool so it can do more work without overheating. A cooler processor is a more efficient processor, meaning it performs better.
However, unlike a PC or server rack, a phone is a compact system. There’s not enough space to heat water and then pump it elsewhere for cooling. Instead, a vapor chamber is used—a thin, hollow chamber, typically made of copper or stainless steel, with a small amount of liquid inside. When the liquid inside heats up, it turns into a gas, which then expands outward, dispersing the heat throughout the phone’s body rather than holding it close to the processor. As it moves away from the heat source, the vapor cools and turns back into a liquid.
Because the chamber is sealed, the liquid cannot evaporate or leak, meaning that theoretically, the liquid can circulate indefinitely throughout the phone’s lifespan. Most manufacturers also use some kind of heat sink, such as thin sheets of graphite or copper. Or, as with the new iPhone 18 Pro, both.
Why are vapor chambers important for smartphones?
Cooling a phone is a huge challenge compared to other electronic devices you might own, simply because they’re so small yet so powerful. A mid-range laptop like the MacBook Air might get by with a combination of thermal heatsinks, a metal case, and low-heat processors to stay operational, while high-powered gaming laptops have room for large, bulky fans.
However, your phone needs to fit in your pocket, and a significant portion of the internal space must be dedicated to the battery to ensure it lasts all day. With all the processors, sensors, and antennas required for a phone, there’s very little space left for heat dissipation. This is why phones typically don’t have processors as powerful as tablets or laptops. While it’s not physically impossible to fit a powerful chip into a pocketable device, without proper heat dissipation, it will likely generate so much heat that it fails, making your phone too big for your pocket.
This heat dissipation is especially important if you live in a warm climate. For example, I live in Texas. Even when I’m driving in an air-conditioned car, if my phone is exposed to direct sunlight, it can start to overheat. When I had a Pixel 6 Pro, it would sometimes shut down (and the navigation would also shut down) simply because it wasn’t in the shade. After upgrading to the Pixel 9 Pro, which has a vapor chamber, I no longer noticed this issue—though this is, of course, just my personal experience.
How to consider the presence of vapor chambers when buying a phone
Apple claims the iPhone 18 Pro’s vapor chamber has three times the surface area of the previous generation, which should theoretically mean better cooling and, therefore, better performance. But does this mean you should choose a phone based on vapor chamber size or whether it even has one?
Well, yes and no. It turns out that Android phones outside of the Apple ecosystem have been using vapor chambers for years , and you might not even have noticed. Vapor chambers are becoming increasingly common, so unless you have an older phone that frequently overheats or are planning to buy a phone several generations older, you probably don’t need to specifically check whether your phone has one.
Whether bigger is necessarily better is also debatable. All other things being equal, yes, a larger vapor chamber will dissipate heat better and cool the phone. But all other conditions are rarely equal. A larger vapor chamber also means the manufacturer can install a more powerful processor and still achieve the same thermal performance. So, theoretically, the phone may be equally likely to overheat, but it will prevent it more effectively.
Finding the optimal balance between processing power and heat dissipation is a task best left to engineers and dedicated enthusiasts. But there are some important lessons for the average user. First, if you live in a warm climate, better heat dissipation is always better. Your phone doesn’t run at full power all day, but the Texas sun does. So, if you’re concerned about overheating in your region, check out phone reviews to see how well they handle heat. More importantly, consider your device’s power consumption needs before purchasing. If you only use your phone for watching TikTok and replying to emails, you probably don’t need a powerful processor, but if you plan to edit 4K video or play graphically demanding mobile games, improved heat dissipation may be beneficial.