Review of the Slimmest Mobile Phones in 2025

In 2025, the smartphone industry has pushed the boundaries of design, with manufacturers competing to create the slimmest devices without compromising performance. Ultra-thin smartphones are not just about aesthetics—they offer portability, comfort, and a premium feel. This blog post reviews the top five slimmest mobile phones available in 2025, highlighting their key features, specifications, and trade-offs. Whether you're a tech enthusiast or someone seeking a sleek, pocket-friendly device, these phones are setting the standard for slim design.

1. Apple iPhone 17 Air

Thickness: 5.6mm
Weight: 146g
Key Features:

• 6.6-inch Super Retina XDR display with ProMotion (1Hz–120Hz refresh rate)
• A19 Bionic chip
• 48MP Fusion camera
• Face ID, emergency SOS via satellite, UWB Gen2
• Scratch-resistant glass protection

The iPhone 17 Air is Apple's thinnest smartphone to date, measuring just 5.6mm. Despite its slim profile, it delivers flagship performance with the A19 Bionic chip, ensuring smooth multitasking and gaming. The vibrant 6.6-inch display supports ProMotion for adaptive refresh rates, making it ideal for both media consumption and productivity. However, the ultra-slim design may limit battery capacity, potentially affecting endurance compared to thicker models. This phone is perfect for minimalists and iOS fans who prioritize portability and premium build quality.

2. Samsung Galaxy S25 Edge

Thickness: ~5.7mm
Weight: 162g
Key Features:

• 6.2-inch Dynamic AMOLED 2X display
• Snapdragon 8 Elite (3nm, co-engineered with Qualcomm)
• 200MP main camera with advanced AI features
• Titanium build with Gorilla Glass Ceramic 2
• Galaxy AI (Audio Eraser, Auto Trim, Now Brief)

Samsung's Galaxy S25 Edge is a standout in the slim phone race, marketed as the sleekest Galaxy design ever. Its titanium frame and Gorilla Glass Ceramic 2 ensure durability without adding bulk. The 200MP camera, enhanced by Galaxy AI features like Audio Eraser for video editing, makes it a favorite for content creators. While its battery life is decent, it ranks lower than some competitors due to the slim form factor. This phone is ideal for Android users seeking a balance of cutting-edge design and top-tier camera performance.

3. Vivo X100 Ultra Slim

Thickness: ~6.0mm
Weight: ~150g
Key Features:

• 3nm chipset with AI-driven load balancing
• Graphene-enhanced battery
• Periscopic optical lenses for high zoom
• AMOLED display with high brightness
• Advanced thermal management with graphene heat spreaders

Vivo’s X100 Ultra Slim is an engineering marvel, leveraging nanotechnology and a 3nm chipset to maintain performance in a sub-6mm chassis. Its graphene-enhanced battery and heat spreaders address common issues like overheating and battery life in slim devices. The periscopic lenses deliver impressive zoom capabilities, making it a strong choice for photography enthusiasts. However, its availability may be limited in some markets. This phone suits users who want cutting-edge technology in an ultra-thin package.

4. OPPO Find N5 (Unfolded)

Thickness: 4.21mm (unfolded), 8.93mm (folded)
Weight: ~190g
Key Features:

• 7.6-inch inner AMOLED display, 4.0-inch outer display
• Snapdragon 8 Elite chipset
• 50MP triple camera system with Leica enhancements
• 5110mAh battery with 67W fast charging
• Near-invisible crease on foldable display

The OPPO Find N5 is the slimmest book-style foldable when unfolded, measuring just 4.21mm. Its innovative hinge and lightweight materials make it feel less bulky than other foldables. The 5110mAh battery is impressive for its size, supporting a full day of use, and the Leica-enhanced cameras deliver stunning photos. However, its folded thickness and higher price point may deter some buyers. This phone is ideal for those who want a foldable device with a premium, slim design.

5. Tecno Spark Slim (Concept)

Thickness: 5.75mm
Weight: Not specified
Key Features:

• Large AMOLED display
• Dual rear cameras
• Battery larger than Galaxy S25 Ultra
• Advanced cooling mechanisms (speculative)

The Tecno Spark Slim, showcased at MWC 2025, is a concept device billed as the industry’s slimmest phone at 5.75mm. It promises a large screen and a battery surpassing the Galaxy S25 Ultra’s capacity, but specific details like processor and camera specs remain undisclosed. The main concern is potential overheating due to limited space for cooling systems. As a concept, it may not be widely available, but it signals the future of ultra-thin designs. This phone is for early adopters excited about experimental tech.

Trade-Offs of Ultra-Slim Designs

While these phones excel in portability and aesthetics, slim designs often come with compromises:

• Battery Life: Thinner phones may have smaller batteries, leading to shorter usage times. Innovations like graphene batteries (Vivo) and AI-driven power management help mitigate this.
• Thermal Management: Limited space for cooling systems can cause overheating during intensive tasks like gaming. Advanced materials like graphene heat spreaders (Vivo) and optimized chipsets address this to some extent.
• Camera Hardware: Slim phones may sacrifice larger sensors or periscope lenses, though models like the Galaxy S25 Edge and Vivo X100 Ultra Slim maintain high-quality imaging.
• Durability: Ultra-thin designs require robust materials like titanium or Gorilla Glass to ensure structural integrity, as seen in the iPhone 17 Air and Galaxy S25 Edge.

The slimmest smartphones of 2025, led by the iPhone 17 Air, Galaxy S25 Edge, and Vivo X100 Ultra Slim, showcase remarkable engineering feats. These devices combine sleek designs with powerful processors, advanced cameras, and innovative materials to minimize traditional trade-offs. Foldables like the OPPO Find N5 push the boundaries further, while concept devices like the Tecno Spark Slim hint at an even thinner future. When choosing a slim phone, consider your priorities—whether it’s camera quality, battery life, or portability—and select the model that best fits your lifestyle.

For the latest updates and pricing, check out trusted retailers like Amazon India or manufacturer websites like Samsung and Apple. Share your thoughts in the comments— which slim phone are you eyeing for 2025?