The world’s thinnest phone was just revealed, but a new iPhone 17 Air leak suggests it could be even slimmer

• Tecno has revealed the world's thinnest slab phone, the 5.75mm Spark Slim
• A new iPhone 17 Air leak suggests Apple will beat this with a 5.44mm chassis
• We're still waiting for any official information about the iPhone 17 Air

Chinese phone maker Tecno has revealed the world’s thinnest slab phone at MWC 2025, but a new leak suggests the much-rumored iPhone 17 Air could be even thinner.

The Tecno Spark Slim measures just 5.75mm thick at its thinnest point, not including the protruding camera bump, and packs an impressive spec sheet into its svelte frame – the Spark Slim sports a 6.78-inch OLED screen with 144Hz refresh rate, dual 50MP main and ultra-wide cameras, and a 5,200mAh battery capacity.

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However, Tecno may lose the title of world’s thinnest candy-bar phone sooner rather than later if a new iPhone 17 Air leak is to be believed.

Images shared by notable tipster Majin Bu on X (formerly Twitter) appear to show a polymer or resin dummy model of the iPhone 17 Air being measured by a digital caliper, with the readout displaying a thickness of 5.44mm.

As with the Spark Slim, this measurement is taken at the phone’s thinnest point and does not account for the camera bump. The leaked image corroborates previous rumors in suggesting the iPhone 17 Air will sport a long, thin camera bar with a single camera.

In fact, the dummy model looks conspicuously similar to CAD renders previously shared by Majin Bu – there was some debate over the plausibility of these renders at the time due to the massively expanded camera housing on the iPhone 17 Pro and iPhone 17 Pro Max, but images shared since have largely followed the rumored designs.

As PhoneArena notes, the new camera bump could push the maximum thickness of the iPhone 17 Air closer to the rumored 5.84mm thickness of the Samsung Galaxy S25 Edge.

A narrow victory

The Galaxy S25 Edge has only had its design revealed so far – we only have rumors and estimates to base specs on – and the iPhone 17 Air has yet to even be confirmed by Apple, so the apparent race to release a thin flagship is still currently a tense wait at the starting blocks.

Unfortunately for Tecno, the smart-looking Spark Slim is unlikely to make much of an impact due to the brand’s global-focused release strategy and lack of US availability.

As for the iPhone 17 Air and Galaxy S25 Edge, I’m hopeful that Apple and Samsung can get the balance right with these new slim phones, and produce handsets worthy of a place on our list of the best phones.

What do you want to see from the iPhone 17 Air? Are you hopeful that thin phones will take off? Let us know in the comments.

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