The New APFS File System
Today's iOS 10.3 update to the iPhone adds the brand-new Apple File System (APFS) to your iOS devices.
The APFS system was announced last year WWDC. It replaces the now 30-year-old hierarchical filing system (HFS, later updated to HFS+) that, until today, was on your iPhone and iPad, and still remains on your Mac. APFS is a much needed modernization, more secure and designed around SSD storage, which didn't even exist when HFS first showed up. In addition to being more secure, the new system should be faster and more efficient, allowing you to save some space.
When Apple first announced this new system, I expected it would be years before we saw it on iPhones. The iPhone is the lifeblood of Apple and changing file systems can sometimes cause problems. Now here we are less than 12 months after announcement and Apple’s installing APFS across all iPhones and iPads. I spoke to a few friends that are more knowledgeable about these things than me and they explained that implementing APFS was easier on iOS because of the way the operating systems is already so locked down.
Following my usual “fire, ready, aim” philosophy about these things, I already updated all of my iOS devices and while the update took a while (converting a file system is never a fast process), everything went just fine and devices are all working just like before. Indeed, I'm writing this post on my updated iPad Pro.
Hopefully this success is a sign that we will see the APFS deployed on the Mac in the next year.