Are ‘slim’ smartphones about to make a comeback? i doubt it.

What year is this? Are ultra-thin phones about to return to fashion after a decade-long absence? If the latest rumors are to be believed, they are. Apple is said to be preparing the iPhone 17 “Air” next year, and Samsung the Galaxy S25 “Slim” as part of its upcoming flagship launch.

It’s still early days for these rumours, so take them with a pinch of salt. These speculations do not indicate how well Apple and Samsung plan to manufacture these models, as they could only be thin compared to their siblings. I wouldn’t call the 7.6mm Galaxy S24 a chunky phone, and would removing 0.5mm make the phone look much different? Absolutely not. However, previous attempts to slim down phones have seen rare phones like 2014’s Vivo X5 Max end up thinner than 5mm. If Apple and Google can get that far, they will be far leaner than today’s leading companies. The question is: but why?

Well, for starters, major Chinese brands own the space. Take a look at recent affordable phones like the HONOR 200 Lite, which is less than 7mm thick, and the OPPO Reno12 Pro, which is just a hair thinner. The equivalent large-screen iPhones and Galaxy devices are all closer to 8mm and thicker once you get into the same price brackets as these brands. While many consumers may not even notice a little extra heft in their phones, Apple and Samsung have their eyes on the lucrative aesthetically pleasing Chinese market, where every millimeter saved is made for extra design points. Slim phones could be their golden ticket.

For Apple, the iPhone 17 Air is also said to be a precursor to its long-awaited foldable ambitions. The phone is rumored to feature a thinner, more efficient Novatek OLED panel, which would be an important development to make any iPhone as foldable and portable as current competitors. For example, the HONOR Magic V3 is only 4.35mm thick when opened flat and 9.3mm thick when closed, and the Huawei Mate XT Ultimate is 4.75mm thick. When you fold a phone in half, thinness matters a lot.

For Samsung, which already has well-established Z Fold and Z Flip lines, the Galaxy S25 Slim may also be linked to its foldable ambitions. The Galaxy Z Fold Special Edition has taken the Z Fold 6’s relatively closed thickness from 12.1mm to 10.6mm. Bringing these same improvements to a traditional flagship form factor provides an easy way to at least appear innovative in today’s stale hardware market.

Naturally, thin phones leave less room for flagship hardware specifications. Batteries have to be thinner, which means sacrificing capacity, although this is a bit less of an issue with recent advances in batteries. There’s less room for large heat sinks, which seems necessary with today’s high-performance chips. Not to mention the possibility of the camera being increased in size or replaced with smaller, lower quality sensors to fit. You simply can’t have it all.

Thin is the antithesis of a high-spec smartphone, which is undoubtedly why the iPhone 17 Air falls at the lower end of Apple’s next-gen portfolio. Aside from foldable devices, it will likely be years before Apple can get a thin form factor up to the ultra-premium tier. Even then, a thicker phone will always be able to pack more. However, with the iPhone Mini out to pasture and Plus models struggling for mindshare, the more affordable Air model may find a warmer reception.

Likewise, Samsung is struggling to find a key distinction between its increasingly similar base models and the Galaxy S FE models. Maybe the Slim will stand out with more affordable specs? I think it’s worth the gamble.

Or maybe not. There is no clear indication that consumers are particularly insatiable with pocket phones. Countless attempts at compact models have failed to strike a chord with consumers despite reviewing well and having at least a niche following. Just look at the iPhone Mini or Sony Compact models mentioned above; Sales volume is not there. Of course, smaller phones don’t address the same market as sub-6-inch displays, but they never really took off when the formula was last tried a decade ago, either. I don’t think all that has changed much since then.

Battery life, photography capabilities, and affordability still rank high on consumer wish lists. Lesser phones are unlikely to meet any of these needs as well as current models do, let alone all of them. While thinness is important for foldable devices, it’s not an issue for classic glass panels. However, I would be happy to be surprised, if these phones turn out to be real.