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title: 'ProMotion Killer: How Tempered Glass Can Affect iPhone’s 120Hz Smoothness (Motion Blur Test)'

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Apple’s ProMotion display is one of the iPhone’s standout features, offering buttery-smooth 120Hz refresh rates for scrolling, gaming, and animations. But there’s a catch: not all tempered glass protectors preserve that silky experience. To see the difference, we ran a motion blur test comparing scrolling on naked screens vs. screens with various tempered glass options.

The Setup

We used slow-motion video capture to observe:

Naked iPhone display at 120Hz

High-quality tempered glass (Gadgetshieldz)

Budget tempered glass from generic brands

We focused on:

Scroll fluidity

Motion blur during fast swipes

Overall visual sharpness

What We Found
Naked Screen

The naked iPhone display was flawless: smooth scrolling, zero blur, and fast touch response. ProMotion lived up to the hype.

Budget Tempered Glass

Even thin, cheap protectors introduced noticeable drag and slight ghosting. Fast scrolling revealed motion blur, making animations look less fluid. Gamers and frequent scrollers immediately noticed a difference.

Premium Tempered Glass (Gadgetshieldz)

Interestingly, high-quality tempered glass minimized performance loss. Motion remained smooth, touch responsiveness was excellent, and scroll behavior felt almost identical to the naked display. Minor differences were only detectable in side-by-side slow-motion comparisons.

Why This Happens

The effect stems from a combination of:

Glass thickness: Thicker layers increase the distance between the finger and the display, slightly altering touch precision.

Optical clarity: Lower-quality glass can reduce transparency, introducing subtle motion blur.

Surface coating: Poor oleophobic or anti-glare coatings can interfere with swipe fluidity.

Premium options like Gadgetshieldz [iPhone tempered glass](https://gadgetshieldz.com/collections/iphone-tempered-glass) are engineered to minimize these effects while maintaining protection.

Real-World Implications

For everyday users, most protectors feel fine. But for:

Gamers relying on fast swipes

Photographers or designers noticing subtle animation artifacts

Anyone who values display fluidity above all else

Choosing the right tempered glass matters. The wrong protector can negate the benefits of a 120Hz display, turning smooth scrolling into slightly sluggish motion.

Key Takeaways

Not all tempered glass is equal: Cheap protectors can compromise ProMotion smoothness.

Premium glass helps preserve 120Hz fluidity: High-quality options like Gadgetshieldz maintain clarity, touch accuracy, and visual smoothness.

Test before trusting: If 120Hz scrolling is important, always compare protectors in motion.

Conclusion

Tempered glass doesn’t have to kill the ProMotion experience—but quality matters. High-grade options like Gadgetshieldz [iPhone tempered glass ](https://gadgetshieldz.com/collections/iphone-tempered-glass)strike a balance between screen protection and fluid, buttery-smooth display performance.

With the right protector, your iPhone can stay safe without sacrificing the magic of 120Hz scrolling.