It's amazing to consider just how much the iPhone has changed from its original release in 2007 to its current iterations, the iPhone 6 and iPhone 6 Plus. In fact, the best way to view that evolution is through a speed test, pitting every generation of iPhone against each other.

That's exactly what YouTube channel EverythingApplePro did, pitting the iPhone 2G against each generation of iPhone, including the most current models.

The test also goes through GeekBench 3 results for every device that will run that app (sorry, iPhone and iPhone 3G). Keep an eye on that iPhone 5S when you watch the video above.

The GeekBench results are particularly interesting, as they show that raw specs only tell part of the story. Every iPhone since the iPhone 5 has had 1GB of RAM, yet the iPhone 6 and 6 Plus are more than twice as fast as the iPhone 5 — according to GeekBench, that is. For those who want to use spec sheets to compare performance, this is a great example of why a number can be totally arbitrary.