Tecno Spark Slim Vs iPhone 17 Air Vs Samsung Galaxy S25 Edge: Fierce Fight For Thinnest Smartphone Crown

Tecno Spark Slim Vs iPhone 17 Air Vs Samsung Galaxy S25 Edge: As fierce fight rages, who will get the thinnest smartphone in the world crown. While industry heavyweights like Samsung, Xiaomi, and Lenovo have showcased unique innovations at the 2025 Mobile World Congress, a relatively lesser name managed to steal the show with its concept. Introducing Tecno Spark Slim, a concept phone by China-based Tecno, which is currently being hailed as the thinnest smartphone in the world.

But how does it hold up when it comes to a comparison with the rumoured iPhone 17 Air and Samsung Galaxy S25 Edge, which are both being touted as "slimmer than 'em all" in varied reports?

On its showcase at MWC, the Tecno Spark Slim had an incredible thinness measuring 5.75mm. If this concept were to go into production, it'll be a smartphone slimmer than many pencils. It is also among the lightest smartphones ever displayed, weighing only 146 gm. 

While the phone looks lean, it packs a punch with its features, which are often not found on slim phones for want of space: 6.78-inch AMOLED screen with 144Hz refresh rate, Corning’s Gorilla Glass, ceramic/stainless steel back, 5,200mAh battery at only 4.04mm thick, 50MP dual primary camera/13MP selfie shooter, and a powerful octa-core chipset.

At the MWC 2025, Samsung too showcased the Samsung Galaxy S25 Edge, claiming it is the slimmest Galaxy S series yet. The phone, which was unveiled at Galaxy Unpacked in January, will likely launch in May. 

Now, while the Galaxy S25 Edge was earlier claimed to be 6.4mm thick (which would have made it far thicker than the Spark Slim), recent reports claim it could be as thin as 5.84mm and weigh less than 162 gm. Even if this holds true, the Tecno Spark Slim would still outshine Samsung Galaxy S25 Edge when it comes to size.

iPhone 17 Air is another story altogether. The most recent leaks indicate it could measure a mere 5.44mm, beating both Spark Slim and Edge hands down to become the “thinnest” smartphone.

The "Twist"

However, in a twist of sorts, this measurement excludes the camera bump, which when added could bring the thickness to around 5.84mm, similar to the Edge. So the iPhone 17 Air might not take the “slimmest” crown after all.

Whether or not the Tecno Spark Slim will see the light of day is up in the air though. Despite the hype, it is still a concept phone with no clear indications of mass production or a launch date. The only smartphone that looks likely to launch is the Samsung Galaxy S25 at the moment,