The hardware engineering and software coordination behind 3D Touch in the iPhone 6S is impressive. It’s such an Apple feature. Executed with exquisite diligence because they control the whole stack. Marvelous.

But you know what, it’s not my favorite feature of the 6S. That honor belongs to the low-tech, behind-the-curve addition of an extra gigabyte of RAM. Something that probably cost Apple just a few extra dollars per phone and almost no engineering prowess. (Compare that to the probably hundreds of millions in revised tooling, advanced development, and more needed for 3D Touch.)

Doubling the RAM means apps aren’t constantly being swapped in and out. Which means switching between them is super fast more of the time. Which in turn makes the whole phone feel much better over the course of a day.

It’s been repeated ad nauseam, but it’s still so hard to internalize for most product people: Speed is a feature.

Usually, it’s one of the most important features. Yet it’s also one of the hardest to get right. Chiefly because every other feature is generally at war with speed. Any excess CPU cycles are quickly captured by new, advanced, and ultimately slowing features. Extra cycles are like a surplus government budget: The constituency is going to have a thousand ideas for how to spend it.

It’s not easy to get this balance just so. You have to be fast at what people want and expect. Being the fastest phone running iOS5 or Window OS isn’t going to get you any business.

Comparing this RAM apple and that 3D Touch orange, though, is also a worthwhile reminder that good product design doesn’t deal in distinct categories. It’s all a fruit salad! Customers just want it to be delicious and nutritious.