Tecno Spark Slim concept phone is less than 6 millimeters thick

How thin is too thin?

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In brief: A slim and light version of the iPhone is expected later this year but a rival handset maker out of China could beat Apple to the punch. Tecno Mobile has announced its Spark Slim, an ultra-thin concept smartphone set to debut at Mobile World Congress in Barcelona next week.

The Spark Slim features a 6.78-inch 3D curved AMOLED display with a 144Hz refresh rate and a peak brightness rating of 4500 nits. Tecno said it will be powered by an upcoming (yet unnamed) high-performance octa-core processor, but we do not know how much memory or storage it will ship with. We do know the phone features a 5,200mAh battery with 45W fast charging, dual 50-megapixel rear-facing cameras, and a 13-megapixel front-facing shooter for selfies and video calls.

The handset's standout feature, however, is its thin profile which measures just 5.75mm at its thinnest. For comparison, Apple's latest iPhone 16 and iPhone 16e are significantly thicker at 7.8mm. A standard No. 2 pencil is around 7mm thick. Tecno did not say how much the phone weighs, but noted it is crafted of recycled aluminum with a stainless steel unibody.

For years, smartphones trended toward increasingly thinner designs, but most manufacturers eventually shifted focus to other features like camera modules. While aesthetically pleasing to some, a thinner chassis leaves less room for key internal hardware like the battery. Slim handsets with large screens are also more prone to physical damage like bending in a pocket. Hopefully the Spark Slim is rigid enough to withstand daily use without bending, as we don't need another "bendgate" controversy like Apple had with its iPhone 6 Plus years ago.

Mobile World Congress, the mobile industry's premiere trade show, kicks off on March 3 and runs through the 6th in Barcelona, Spain. Tecno Mobile will have the Spark Slim on display at booth 6B11. The show is open to the general public and with any luck, we will learn more about this intriguing ultra-slim come next week.