TecnoOrange 
When you buy a phone, the spec you always check is “128GB” or “256GB” of storage. But almost nobody looks at what type of storage it has. And the difference between UFS 3.1 and UFS 4.0 is more important than you think. It directly affects app loading speed, game load times, and even battery life. Here’s the breakdown without unnecessary jargon.
Table of contents
Table of contents
What is UFS and why does it matter
UFS stands for Universal Flash Storage, and it’s the internal storage standard used by modern phones. Think of it as your phone’s SSD: it stores your photos, apps, games, and operating system.
Before UFS, phones used eMMC (embedded MultiMediaCard), which was much slower. UFS changed the game because it allows simultaneous reading and writing (full duplex), while eMMC could only do one thing at a time.
The difference between UFS generations isn’t just theoretical. A phone with UFS 4.0 opens apps faster, loads game levels quicker, and processes HDR photos faster than one with UFS 3.1. All because the storage can read and write data at higher speeds.
Heads up: Don’t confuse UFS with storage capacity. A 256GB phone with UFS 3.1 is slower than a 128GB phone with UFS 4.0 in read/write operations. Capacity and speed are different things.
UFS 4.0 is the latest version, released in 2022 by JEDEC. It started appearing in flagship phones in late 2023 and in 2026 is the standard for high-end devices.
Read and write speeds
Here’s the main and most tangible difference.
UFS 3.1
- Sequential read: up to 2,100 MB/s
- Sequential write: up to 1,200 MB/s
- Random read: up to 100,000 IOPS
- Random write: up to 70,000 IOPS
UFS 4.0
- Sequential read: up to 4,200 MB/s
- Sequential write: up to 2,800 MB/s
- Random read: up to 200,000 IOPS
- Random write: up to 100,000 IOPS
The difference is 100% in sequential read and over 130% in sequential write. This isn’t an incremental improvement — it’s a real generational leap.
| Specification | UFS 3.1 | UFS 4.0 | Improvement |
|---|---|---|---|
| Sequential read | 2,100 MB/s | 4,200 MB/s | +100% |
| Sequential write | 1,200 MB/s | 2,800 MB/s | +133% |
| Random read | 100K IOPS | 200K IOPS | +100% |
| Energy efficiency | Baseline | 46% better | Significant |
| Bandwidth per lane | 11.6 Gbps | 23.2 Gbps | +100% |
Energy efficiency
This is a less well-known but very relevant difference. UFS 4.0 consumes significantly less energy than UFS 3.1 for the same operations.
UFS 4.0 offers a 46% improvement in energy efficiency per MB transferred. This translates directly to longer battery life, especially when storage is very active (loading games, copying large files, or processing video).
Samsung, which manufactures UFS 4.0 chips, claims their chips consume only 1.2mA per MB/s of read speed, compared to 2.2mA for UFS 3.1. That may seem small, but accumulated throughout the day, it represents a notable energy saving.
Pro tip: If battery life matters to you, UFS 4.0 is a factor to consider when buying a phone. It’s not as visible as battery size, but it contributes to overall autonomy.
The efficiency comes from two factors: a more advanced manufacturing node and a more optimized communication protocol. UFS 4.0 uses more efficient signals that require less voltage to transmit the same amount of data.
Real-world impact on phone use
Theoretical speeds are great, but what does it mean in daily use?
App opening
A phone with UFS 4.0 opens apps 15-25% faster than one with UFS 3.1. For small apps like WhatsApp, the difference is imperceptible (both are instant). For heavy apps like Instagram, Lightroom, or games, the difference is noticeable.
Game loading
This is where UFS 4.0 shines. Modern games have several GB of resources loaded when starting levels. With UFS 4.0, loading screens are shorter. I’ve measured 5-15 second differences in initial load times for games like Genshin Impact.
File copying
If you move lots of files between your phone and PC, UFS 4.0 makes a visible difference. Copying 10GB of photos to a PC is 30-40% faster.
4K/8K video recording
High-resolution video recording needs to write data at high speeds. UFS 4.0 allows 8K recording without buffering or interruptions, something UFS 3.1 may struggle with during long recordings.
| Scenario | UFS 3.1 | UFS 4.0 | Difference |
|---|---|---|---|
| Open Instagram | ~0.8s | ~0.6s | ~25% faster |
| Load game level | ~15s | ~10s | ~33% faster |
| Copy 10GB to PC | ~45s | ~30s | ~33% faster |
| Boot phone | ~25s | ~18s | ~28% faster |
Phones with UFS 4.0 in 2026
In 2026, virtually all flagship phones use UFS 4.0. Some upper mid-range models have also started adopting it.
Phones with UFS 4.0
- Samsung Galaxy S24/S25 series
- iPhone 16 Pro / Pro Max
- OnePlus 12/13
- Xiaomi 14/15
- Google Pixel 9 Pro
- ASUS ROG Phone 8/9
Phones with UFS 3.1 (upper mid-range)
- Samsung Galaxy A55/A56
- Xiaomi 13T / 14T
- Nothing Phone 2/3
- Google Pixel 8a/9a
- Motorola Edge 40 Neo
Heads up: Not all variants of a model use the same UFS version. Sometimes the 128GB version has UFS 3.1 and the 256GB version has UFS 4.0. Check the exact specs before buying.
UFS vs microSD card storage
A question I get a lot is whether UFS speed matters when you also use a microSD card. The short answer: yes, but they’re different things.
Your microSD stores photos, videos, and personal files, but apps, the operating system, and cache are stored on the internal UFS storage. When you open an app or load a game level, the phone reads from UFS, not the microSD. That’s why a phone with UFS 4.0 and a slow microSD will still be fast for the operations that matter.
| Storage | Main use | Typical speed |
|---|---|---|
| UFS 4.0 internal | System, apps, cache | 4,200 MB/s read |
| UFS 3.1 internal | System, apps, cache | 2,100 MB/s read |
| MicroSD UHS-I | Photos, videos, files | 90-170 MB/s read |
| MicroSD UHS-II | 4K videos, fast files | 150-300 MB/s read |
Pro tip: If you record a lot of video, use internal recording (UFS) and then transfer files to the microSD or PC. Recording directly to microSD limits quality and can cause buffering.
Future of mobile storage: what comes after UFS 4.0?
JEDEC is already working on the next generation. UFS 5.0 is in development and promises read speeds up to 6,400 MB/s, with a new communication protocol that further reduces latency.
There are also rumors about CXL (Compute Express Link) based storage for mobile devices, though this is more speculative and probably won’t arrive until 2028 or later.
What’s certain is that mobile storage will keep closing the gap with desktop SSDs. In a few years, the difference between a phone’s storage and a PC’s will be practically imperceptible for most users.
My advice: don’t wait for “the next thing” to buy. UFS 4.0 is already excellent and will last the entire useful life of your phone without performance issues.
FAQ: Frequently asked questions
Is it worth paying more for UFS 4.0?
If you use your phone intensively (gaming, photography, video), yes. For basic use, UFS 3.1 is still excellent and the difference will be imperceptible.
Can I check what UFS my phone has?
Yes. Download “A1 SD Bench” or “AndroBench” from the Play Store and run a storage benchmark. If read speed exceeds 3,500 MB/s, you have UFS 4.0.
Does UFS 4.0 run hotter than UFS 3.1?
No. Being more efficient, it generates less heat per operation. Operating temperature is similar or lower.
Does UFS 4.0 last longer than UFS 3.1?
Both have similar write cycles. Storage durability depends more on the NAND chip quality than the UFS version. There’s no significant difference in lifespan.
Conclusión
The difference between UFS 3.1 and UFS 4.0 storage is real and tangible: double the read speed, 46% more energy efficiency, and better performance in demanding tasks. If you’re buying a flagship phone in 2026, make sure it has UFS 4.0. For mid-range phones, UFS 3.1 remains very competent and shouldn’t be a deciding factor.