iPhone X vs Samsung Galaxy S9 - Complete Review

Battery Capacity: 2716 mAh (iPhone X) / 3000 mAh (Galaxy S9)
Dimension: 143.6 x 70.9 x 7.7 mm (X) vs 147.7 x 68.7 x 8.5 mm (S9)
Chipset: Apple A11 Bionic vs Snapdragon 845 / Exynos 9810
Storage: 64GB/256GB (NVMe) vs 64GB/128GB/256GB (UFS 2.1)
Camera: Dual 12MP (Telephoto) vs Single 12MP (Variable Aperture)
OS: Up to iOS 16.7 vs Android 10 (One UI 2.5)


iPhone X vs Samsung Galaxy S9 - Complete Review & Comprehensive Buying Guide

When discussing the most pivotal smartphones of the last decade, the conversation inevitably lands on the iPhone X and the Samsung Galaxy S9. Even years after their initial release, these devices represent a fascinating fork in the road for mobile technology. The iPhone X was the revolutionary leap that introduced the notch and FaceID, effectively killing the home button. Conversely, the Galaxy S9 was the perfectionist—refining the curved edge design, retaining the headphone jack, and introducing variable aperture cameras.

For budget-conscious buyers, tech enthusiasts looking for a secondary device, or collectors, the choice between these two is no longer about "Apple vs. Android" marketing hype. It is about practical usability, repairability, and software longevity in the current era. This technical analysis dissects both devices to determine which flagship retains its crown today.

Expert Opinion Snapshot: The Executive Summary

Before diving into the microscopic details, here is the high-level verdict for the pragmatic buyer.

The Case for iPhone X: You should choose the iPhone X if you prioritize software fluidity and social media optimization. Despite being older, the A11 Bionic chip still handles Instagram and Snapchat better than the S9. It also supports iOS 16, offering a much more modern interface than the S9's Android 10. However, be prepared for thermal throttling and average battery life.

The Case for Galaxy S9: Choose the S9 if you are a multimedia consumer or an audiophile. The 1440p AMOLED screen is technically sharper than the iPhone's, and the inclusion of a 3.5mm headphone jack with a high-quality DAC is a rare luxury today. It also supports expandable storage via microSD, which is crucial if you buy the base 64GB model.

Full Technical Specifications Comparison

Feature iPhone X Samsung Galaxy S9
Screen Tech 5.8" Super Retina OLED (1125 x 2436) 5.8" Super AMOLED (1440 x 2960)
Pixel Density ~458 ppi ~570 ppi (Sharper)
Processor Apple A11 Bionic (10nm) Snapdragon 845 / Exynos 9810 (10nm)
RAM 3GB 4GB
Biometrics Face ID (3D Structured Light) Rear Fingerprint + Iris Scanner
Water Resistance IP67 (1m for 30 min) IP68 (1.5m for 30 min)

Ergonomics, Build & Display Technology

This generation marked the peak of the "Glass Sandwich" era. Both phones feel incredibly premium, utilizing stainless steel (iPhone X) and aluminum (Galaxy S9) frames.

The Display Battle: Surprisingly, Samsung manufactured the OLED panels for both devices, but the calibration differs. The iPhone X uses "Super Retina" tuning, which prioritizes color accuracy and natural tones. The Galaxy S9, however, pushes for vibrancy and higher peak brightness. The S9 technically wins on resolution (570ppi vs 458ppi), and unlike the iPhone, it lacks a notch, offering an uninterrupted cinematic experience.

Expert Insight: The iPhone X uses PWM (Pulse Width Modulation) at a lower frequency (240Hz) to dim the screen, which can cause eye strain for sensitive users. The Galaxy S9 also uses PWM but generally handles low brightness slightly better due to Samsung's driver implementation.

Performance, Thermals & Gaming

In terms of raw silicon, the Apple A11 Bionic was significantly ahead of its time. Even today, it opens applications with a snappiness that rivals mid-range phones from 2023. The NVMe storage controller in the iPhone X allows for faster read/write speeds than the UFS 2.1 storage found in the Galaxy S9.

Thermal Management: This is a weak point for the iPhone X. The stacked motherboard design traps heat, leading to screen dimming during intensive tasks like GPS navigation or gaming (PUBG/Call of Duty). The Galaxy S9, particularly the Snapdragon version, dissipates heat more effectively, maintaining peak brightness for longer periods.

Software Longevity: The iPhone X officially supports up to iOS 16.7. This means you still have access to most modern app features and security patches. The Galaxy S9 is stuck on Android 10 (One UI 2.5). While functional, many banking apps may soon drop support for this older Android version.

Camera Capabilities: The Dual Lens vs Variable Aperture

The camera philosophy differs drastically here. The iPhone X relies on a dual-camera setup, while the S9 uses a single, highly advanced lens.

iPhone X (Dual 12MP): The secondary telephoto lens provides 2x optical zoom, which is essential for Portrait Mode. Apple's color science remains superior for skin tones and video stabilization. If you shoot video for social media, the iPhone X is the clear winner due to its bitrate handling and dynamic range.

Galaxy S9 (Single 12MP): Samsung introduced a mechanical variable aperture (switching between f/1.5 and f/2.4). In low light, the lens physically opens to f/1.5, letting in massive amounts of light. For night photography, the S9 often outperforms the iPhone X, producing brighter images with less noise. However, without a second lens, its portrait mode (Live Focus) relies entirely on software, which is less accurate than the iPhone's hardware-based depth mapping.

Battery Endurance & Charging Speeds

If you are buying these phones used, battery health is your primary concern.

  • iPhone X: 2716 mAh. Originally good for a day, but degraded units will struggle to hit 4 hours of screen-on time. iOS standby management is excellent, however.
  • Galaxy S9: 3000 mAh. Despite the larger cell, the higher resolution screen and Android background processes drain it quickly.

Both phones support fast wired charging (15W) and Qi wireless charging. Note that the iPhone X requires a Lightning cable, while the S9 uses the now-standard USB-C, making the S9 more convenient for modern setups.

Pre-owned Inspection Checklist

Because these devices use OLED screens, they are susceptible to "burn-in" (permanent ghost images). Use this checklist before purchasing:

Component Test Procedure
OLED Screen Open a pure white image at max brightness. Look for faint icons of keyboards or status bars (Burn-in).
FaceID (iPhone) Attempt to set up a new face. If it fails instantly, the TrueDepth camera is broken (often irreparable).
Touch IC (iPhone) Drag an app icon all over the screen. If it "drops" or gets stuck, the digitizer is failing.
Sensors (Samsung) Dial *#0*# to access the hidden test menu. Check Red, Green, Blue, and Vibration.

Top Alternatives Comparison

If you are considering these phones, you should also look at their immediate successors which offer better value for a slightly higher price.

Alternative 1: iPhone XR. It has an LCD screen (inferior to X) but features the A12 Bionic and significantly better battery life. It is the smarter buy for longevity.

Alternative 2: Galaxy S10e. This phone retains the compact form factor but adds an ultra-wide camera and a newer processor, fixing many of the S9's aging issues.

Critical Advice & Final Verdict

Buying a phone from 2017/2018 requires managing expectations. Neither device will play the latest Genshin Impact at max settings, nor will they last two days on a charge.

The Winner: iPhone X. Despite the Galaxy S9 having superior hardware features like the headphone jack and a notch-less display, the iPhone X wins on usability. The app ecosystem on iOS is more forgiving to older hardware. The A11 Bionic, combined with iOS optimization, ensures the phone remains usable for daily tasks, banking, and social media. It holds its value better and parts are widely available for repairs.

Buy the Galaxy S9 ONLY if: You strictly need a cheap media player, you require a microSD slot for local music/movies, or you are a developer looking for a cheap Android test bench. For a daily driver, the lack of security updates makes it a riskier proposition.

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