Watch Every iPhone Ever Face The Ultimate Speed Test

Get ready to be bummed if you're still on an iPhone 4.

A heroic YouTuber has tested the theory that iPhones get better every year.

You're right if you expected that the brand new iPhone 6S is the best ever, but you might be surprised to see the oldest Apple device outshining some of the more recent models in a startup speed test.

EverythingApplePro found that, when it comes to how fast the phone boots up, the new 6S and 6S Plus devices get there fastest. Interestingly, the 6S is a teeny bit faster than the Plus. 

The normal 6 and 6 Plus devices were next, followed by the 5S -- and then things get weird.

The original iPhone booted up faster than the iPhone 5 and 5C, then the normal iPhone 5, followed by the iPhone 3GS, iPhone 5C, iPhone 4, iPhone 3G and, finally, the iPhone 4S.

In fairness: The iPhone 4S in this demonstration is running iOS 9, the latest version of Apple's mobile operating system. That's probably too much for the older phone to handle comfortably.

"Every single device has been updated and restored to the latest firmware," EverythingApplePro says in the video. "Of course, not all of these run the same firmware, so things are going to be a little different. Some of these don't have the newest and greatest features to load."

In other words, he tried his best to make everything equal across devices, but there are certain limitations.

The full video has plenty of other gems -- the discovery that the iPhone 6S is "18 times more powerful" than the original iPhone, for example. You can watch it below:

Correction: An earlier version of this post said the iPhone 4 in the video is running iOS 9. It is not.