iPhone 6 vs iPhone 6S: The Key Differences
The iPhone 6 and iPhone 6S share the same 4.7-inch display and similar silhouette, but Apple made meaningful upgrades underneath. The 6S introduced a faster chip, a better camera, and a more durable build. If you are choosing between the two today, the differences affect performance, longevity, and daily use more than they do aesthetics.
More from this site
Keep reading the latest coverage
Design and Build Quality
At first glance, the two phones look nearly identical. Both use aluminum frames and glass front panels, and both weigh close to 129 grams. The 6S is fractionally thicker and heavier, which is a direct result of the stronger internal materials Apple added.
7000 Series Aluminum
The iPhone 6S switched to a 7000 series aluminum alloy, the same material used in the Apple Watch. This made the frame more resistant to bending and cracking compared with the original iPhone 6, which gained a reputation for flexing under pressure.
3D Touch
The biggest visible difference is 3D Touch on the 6S. This pressure-sensitive display lets you preview links, emails, and photos with a firm press, and it opens quick action shortcuts from the home screen. The iPhone 6 lacks this feature entirely and relies only on standard touch input.
Performance and Chipset
Apple equipped the 6S with the A9 chip and M9 motion coprocessor, while the iPhone 6 uses the older A8 chip and M8 coprocessor. In benchmarks and real-world use, the 6S is noticeably snappier, with better app launch times, smoother multitasking, and improved energy efficiency.
| Component | iPhone 6 | iPhone 6S |
|---|---|---|
| Chip | A8 | A9 |
| Motion Coprocessor | M8 | M9 |
| RAM | 1 GB | 2 GB |
| 3D Touch | No | Yes |
Camera Upgrades
Both phones shoot 8-megapixel stills, but the 6S improved the sensor, added live photos, and introduced 4K video recording. The front-facing camera also moved from 1.2 megapixels to 5 megapixels, making selfies and FaceTime calls noticeably sharper.
Real-World Impact
For casual photography, the gap is visible in low light and in motion. The 6S captures more detail and handles noise better, while live photos add a short animated clip to every still image. If video matters, 4K recording is exclusive to the 6S.
Battery Life and Software
Apple rated the iPhone 6S battery at 1715 mAh, slightly smaller than the 6S battery, but the A9 chip is more efficient. In practice, daily battery life between the two models is close, though heavy 3D Touch and 4K use can drain the 6S faster.
Both phones stopped receiving major iOS updates, but the 6S made it to iOS 15 while the iPhone 6 stalled at iOS 12. This matters for security patches and app compatibility today.
Which One Still Makes Sense
If you are choosing between a used iPhone 6 and a 6S in 2025, the 6S is the better buy in nearly every category. It lasts longer on software, shoots better photos, and handles everyday tasks with more headroom. The iPhone 6 remains usable for light tasks, but its age shows in performance and app support.