Slim phones could fill the compact phone-shaped hole in our hearts

The return of slim phones will be led by the launch of the Samsung Galaxy S25 Edge and the iPhone 17 Air. Both are yet to be officially announced, but Samsung teased the former for the first time at Unpacked 2025, whereas ample rumors confirm the latter’s existence. Surprisingly, neither Samsung nor Apple is particularly bold or innovative in bringing the latest tech to the market. They wait for the tech to mature before adding it to their flagships.

In search of innovation

Smartphone companies are likely looking for new ways to reignite excitement for the category after compact phones (iPhone 13 Mini, Asus Zenfone 10) and phablets (iPhone 16 Plus) failed to move the needle. Notable Apple analyst Mark Gurman believes that the company’s Air strategy is “a tried-and-true winner” for getting sales.

The value proposition for volumetrically smaller devices has always been around portability and ergonomics. We have seen how unwieldy smartphones have become over the last decade. With the advent of foldables, that trend is unlikely to stop soon. In such a time, compact phones could bring respite to users (and their pinky fingers). Still, if the need were big, the demand should be reflected in the sales figures for such devices.

Historically, a smaller form factor (on either axis) has always meant balancing trade-offs. Physics disallowed the creation of smaller phones without bringing in compromises, like smaller batteries, smaller cameras, and smaller components. Still, things could be different this time around.

The state of technology

Let’s address them one by one. Battery capacities, or rather battery densities, have been trending upwards. At the same time, material breakthroughs allowed for more power to be stored in the same cell footprint. We saw this play out with foldables (another category that balances volumetric trade-offs) and slab phones, such as those from OnePlus and Honor, that use silicon-based anodes instead of graphite. Resultant phones have had batteries with capacities upwards of 6,000 mAh without an increase in size or weight.

Camera hardware progression has been somewhat reserved for giant Ultra phones in recent years. Most regular phones stick to older hardware solutions and use computational photography to bridge the gap. In a time when AI’s role in photography has increased, we feel that cameras shouldn’t be a major hurdle for OEMs to figure out. Most of Apple’s and Google’s latest smartphones use older, smaller sensors to produce incredible results, thanks to better image processing.

Other components are where things get interesting. Since hundreds of millions of smartphones are sold each year, internal components are commoditized. A manufacturer looking for non-standard parts will pay a hefty price as initial fixed cost and capital expenditure without a guarantee of success.

Compact phones had it worse, as the X- and Y-axis dimensions of components are bottlenecks to internal layout designs, not their height and thickness. Since most components (motherboard, chipset, cooling, vibration motors, ports, and buttons) can’t be skipped or miniaturized, the batteries or cameras take a hit.

The time is ripe

Performance and cooling are unlikely to be big problems for manufacturers as they were in the last decade. Silicon designs have come a long way, and the newer manufacturing nodes have enabled more efficient chipsets. Every new chipset generation uses a more advanced manufacturing process to improve performance. However, the same design can be more efficient by having a mix of cores to reduce performance and thermal management for longer battery life. We wouldn’t be surprised to see the 7-core version of the Snapdragon 8 Elite used in the Galaxy S25 Edge.

This is where slimmer phones could be surprise winners. Since they offer the same area as a conventional phone, most components could fit with some smart placement. Making them thinner will require redesigning some parts for performance and safety, along with overhauling the motherboard to accommodate everything. Still, it should be more feasible than designing a compact phone.

For phones or any cuboidal product, lowering the smallest dimension is mathematically the most effective way to lower the space the object occupies. While ergonomic gains are higher in compact phones than slimmer ones, it is not nothing. The allure of thinner devices has always been that they are closely related to a premium positioning. Think about laptops, tablets, smartwatches, and earphones. Slimmer phones look good, but the positioning could be one of luxury more than functionality.

The bigger picture

Think about the iPhone lineup. The Pro models indicate higher performance, while the non-Pro variant is cheaper. The Plus model offers a mix of both while appealing to neither segment. By replacing the Plus with an Air, Apple could make the slimmer iPhone 17 Air more desirable, possibly demanding a higher price.

If we zoom out a little, there’s another advantage of why smartphone makers are suddenly interested in making slimmer phones. Foldables are the next big thing in smartphones, held back mainly by their higher selling prices. By innovating on thinner devices, OEMs can gain valuable understanding and insights into designing phones within constraints.

For a brand like Samsung that sells quite a few foldables, adding a slim option would allow it to realize better economies of scale. The S25 Edge will likely have more parts in common with the Z Fold 6 than the rest of the S25 family. For someone like Apple, an iPhone 17 Air would allow it to test the waters before launching its foldable.