These days smartphones come with eMMC (embedded multimedia card) storage or UFS (Universal Flash Storage). UFS technology is substantially faster than eMMC which is why it is mostly found on flagship or high-end devices, whereas the latter is commonly found on mid-range and budget devices instead.
Now, JEDEC has announced UFS 3.1, the latest version which succeeds UFS 3.0 found on the latest flagship smartphones including the OnePlus 7, Galaxy Note 10, Huawei Mate 30, etc.
The biggest enhancement here would be the improvement in write speed as it affects real-world performance. This would make installing apps and taking photos faster, improving the overall experience.
This kind of technology is already present on SSDs and this improvement brings UFS closer to NVMe SSDs used in iPhones and iPads.