Some people look a little unkindly on the so-called "S" years -- those years when Apple updates the iPhone, but doesn't change how it looks, and then sells that while secretly working on something flashier that will debut 12 months later. I don't think that's exactly fair. Those "S" years are when Apple adds some of its most useful features. Siri? Touch ID? Both valuable additions to the iPhone platform that have since grown in importance. This year we get 3D Touch, a potentially awesome way to interact with iPhones. The thing is, a device's worth isn't just tied up in one feature: It's about how all those moving parts work together. That's why the new 6s and 6s Plus (starting at $649 and $749, respectively, for 16GB models) are such great phones. The combination of much-improved hardware and some polished software makes this year's release far more than just a modest refresh.
The iPhone 6s Plus has 3D Touch, iOS 9, a pair of improved cameras and the powerful A9 chipset, just like its smaller sibling. A long-lasting battery and optical image stabilization for its 12-megapixel rear camera help give the iPhone 6s Plus a slight edge over the regular 6s, although we wish it were a little easier to hold.
Meanwhile, we're still left with the same 16GB, 64GB and 128GB storage options as last year, and you're almost certainly going to want one of the latter two. I was hoping against hope Apple would finally give the 16GB model the heave-ho and raise the baseline to 32GB of space. That was clearly silly of me. Economies of scale aside, iOS 9's smaller footprint and new developer tools like app slicing make the 16GB iPhone a little easier to make do with, though the inclusion of an upgraded 12-megapixel camera, 4K video shooting and animated Live Photos (which are turned on by default) means some will have a tough time keeping free space available.
As it happens, both phones are a touch thicker and heavier than before, but they're still comfortable to hold, and the change in thickness specifically is so subtle that it's nearly imperceptible. As for the weight, the 6s and 6s Plus do indeed feel noticeably weightier: The 6s weighs in at 143 grams, up from 129, while the bigger 6s Plus now comes in at 192 grams, up from 172. Not that that's a bad thing. All told, this is one of the few times an iPhone has gotten beefier (the 4s was slightly heavier than the 4), and I'm actually quite pleased about it. At some point, there has to be a lower limit to how thin a phone can get and still be comfortable to use. I'd much rather see companies abandon that ceaseless march toward cartoonishly thin designs and instead work to make better use of the sizes they've already achieved.
What's more, there's an entirely new vocabulary around this 3D Touch screen. Pressing down to preview something in a little pop-up window -- be it a web link, or an address someone texted you -- is what Apple calls "peeking." Apply just a bit more pressure and the phone will bring up the usual, full-screen app view, in this case a Safari window or a location in Apple Maps. Congratulations, you just "popped" something. You can't use all the same 3D Touch actions if you're using an iPhone 6s Plus in landscape mode. Pressing down on app icons still brings up the menus you'd expect them to -- as evidenced by the GIF above -- but you can't peek/pop addresses or hyperlinks in Messages and Mail while the phone is sideways.
Apple's already laid out guidelines about how developers should implement 3D Touch, and they're basically centered on one key idea: 3D Touch is about helping users do things faster. So far, the vast majority of apps don't yet support 3D Touch, but the ones that do take different approaches as to what you can peek at. Some, like Twitter and Instagram, let you press down on their app icons to bring up those Quick Actions menus for near-instantaneous tweeting and photo sharing. Others, like Dropbox, offer previews of your files when you long-press their filenames in a list, but there's no app icon interaction. OpenTable takes sort of a hybrid approach -- you'll get both an app icon menu and the ability to peek at restaurants' locations in Maps as you're scrolling through the culinary options.
A new kind of touchscreen and some upgraded cameras are one thing, but what about the silicon running under the hood? This year, we've got a new 64-bit A9 chipset thrumming away inside both the iPhone 6s and 6s Plus, which, according to some benchmarking tools, appear to be made up of dual 1.8GHz Typhoon CPU cores, the GPU and the updated M9 co-processor. Apple never comments publicly about how much RAM its phones have, but recent teardowns show that the new iPhones have 2GB, just like the most recent iPad Air and Mini. All together, that's the biggest performance increase from one generation to another that we've seen in a while, and it shows.
I spent most of my time testing the iPhone 6s and 6s Plus by restoring them from recent backups of an iPhone 6 and 6 Plus, and then using them side by side. The difference is obvious: Launching apps, firing up webpages and multitasking were all noticeably smoother on the newer iPhones. This performance gap can still vary a bit; the older iPhones would occasionally get close to 6s speed, but they never fully caught up. The benchmark table below paints a pretty good picture of just how much better the 6s and 6s Plus are at handling graphically intensive tasks like playing games. No dropped frames, no stuttering, no jankiness -- the 6s and the 6s Plus were the clear winners.