When we tested iOS 11 on the iPhone 5S, it was clear that it was slower than iOS 10 had been but that the iPhone 5S’ hardware was fast enough to keep everything usable. That’s especially true if you tempered your expectations: the phone was going on four years old at the time.

But at the time, some of you asked us to test a handful of other older iOS devices, particularly the A7-equipped iPad Air and Mini 2 and the A8-equipped iPhone 6 Plus. In the iPads, the same A7 CPU and GPU that powers the iPhone 5S’ screen has to adequately support a tablet with more than three times as many pixels. And the A8 in the 6 Plus draws a 2208×1242 image which is then downscaled to the phone’s 1080p screen; that means using a CPU that was around 25 percent faster than the A7 and a GPU that was only 50 percent faster to support a phone with 277 percent as many pixels.

The upshot is that those devices can often feel sluggish or laggy compared to subsequent models. Later Apple chips—from the A8X in the iPad Air 2 and the A9 in the iPhone 6S and 6S Plus onward, approximately—remain more than fast enough to run iOS 11 without any huge degradation of performance. But with iOS 12 this year, we’re testing an iPad Mini 2 and iPhone 6 Plus in addition to the old 5S to get an idea of how well Apple was able to improve the responsiveness of these older devices, many of which are still in use as secondary phones and tablets or hand-me-downs (or by people who just see no particular reason to upgrade).

Each device was signed into a test iCloud account and allowed to fully sync mail, bookmarks, notes, and other data before being tested, and every device has a gently used battery that should be unaffected by battery-related slowdowns. In the case of the iPhone 5S, we also have data from last year’s iOS-10-to-iOS-11 comparison—we’re using exactly the same 16GB iPhone to test iOS 12, which means we don’t need to worry about the normal differences between units (like total storage capacity or NAND chips from different manufacturers or manufacturing runs). If trying this at home, your absolute test results may differ slightly from ours, but your relative results should be similar.

App launch times: iPhone 5S

Application iOS 10.3.3 iOS 11.0 iOS 11.4.1 iOS 12.0 GM Difference (%) Safari 1.2 seconds 1.5 seconds 1.44 seconds 1.15 seconds -20.6% Camera 0.9 seconds 0.9 seconds 0.97 seconds 0.81 seconds -16.2% Settings 0.9 seconds 1.3 seconds 1.16 seconds 0.86 seconds -26.1% Mail 1.4 seconds 1.8 seconds 1.67 seconds 1.36 seconds -18.5% Messages 0.8 seconds 1.1 seconds 1.03 seconds 0.89 seconds -14.2% Calendar 0.8 seconds 1.2 seconds 0.94 seconds 0.85 seconds -9.6% Maps 2.2 seconds 3.2 seconds 2.60 seconds 2.32 seconds -10.7% Notes 1.5 seconds 2.0 seconds 1.89 seconds 1.59 seconds -15.9% Cold boot 26.6 seconds 38.6 seconds 27.67 seconds 25.28 seconds -8.7%

Note: iOS 10.3.3 and iOS 11.0 data is rounded to the nearest tenth of a second.

As usual, our first tests compare app launch times. App launch times aren’t necessarily indicative of how a phone will feel to use once the apps are launched, but small increases or decreases in app launch time can have a large performance impact over time. We launched Safari, Camera, Settings, Mail, Messages, Calendar, Maps, and Notes, force-quitting the apps in between launches. The times below represent the average of three launches, which were tracked with a stopwatch. We also tested the boot time of each device.

Jumping from iOS 10.3.3 to iOS 11.0 resulted in a handful of small performance regressions that are marginally improved in iOS 11.4.1, but for the most part iOS 11’s performance has stayed level. By comparison, across the board, iOS 12 performs almost as well as iOS 10, whether you’re launching a lighter app like Settings, a heavier one like Maps, or cold booting your phone. It’s an impressive, noticeable gain and a huge improvement for anyone out there who’s still getting by with a 5S.

iPhone 6 Plus

Application iOS 11.4.1 iOS 12.0 GM Difference (%) Safari 1.23 seconds 1.02 seconds -17.3% Camera 1.0 seconds 0.82 seconds -18.3% Settings 0.95 seconds 0.75 seconds -21.7% Mail 1.27 seconds 1.14 seconds -10.5% Messages 0.79 seconds 0.73 seconds -7.2% Calendar 0.76 seconds 0.67 seconds -11.9% Maps 2.25 seconds 1.88 seconds -16.3% Notes 1.39 seconds 1.18 seconds -15.1% Cold boot 25.49 seconds 22.18 seconds -13.0%

We don’t have data from iOS 10 for the iPhone 6 Plus, but measuring app launch times shows pretty much the same improvements that we saw on the iPhone 5S (and the 6 Plus was already as fast running iOS 11 as the iPhone 5S is after iOS 12’s improvements). The percentage improvements are usually in the 10 to 15 percent range, with a handful of outliers in either direction.

iPad Mini 2

Application iOS 11.4.1 iOS 12.0 GM Difference (%) Safari 1.78 seconds 1.62 seconds -9.0% Camera 1.04 seconds 0.96 seconds -7.1% Settings 1.46 seconds 1.26 seconds -13.5% Mail 2.24 seconds 2.08 seconds -7.4% Messages 1.13 seconds 1.02 seconds -9.2% Calendar 1.14 seconds 0.93 seconds -18.5% Maps 3.54 seconds 2.61 seconds -26.2% Notes 2.54 seconds 2.32 seconds -8.7% Cold boot 27.31 seconds 23.34 seconds -14.5%

The iPad Mini 2’s struggles are apparent in both iOS 11 and iOS 12. The iPad is slower across the board, and though it does benefit from iOS 12, the improvements are a bit smaller than they are for either phone.

Keyboard display speed—no difference we can see

We also tried to test Apple's claims of a faster keyboard display, which the company says is up to 50 percent faster in iOS 12 (based on comparing a beta build of iOS 11.4 to a beta build of iOS 12.0 on an iPhone 6 Plus). Using another iPhone, we shot a 240FPS slow-mo video to measure how long it took for the keyboard to spring up after tapping the screen. However, though we tested all three of our test devices in both Notes and Safari, we weren't able to detect a measurable difference in keyboard load time between iOS 11.4.1 and the GM build of iOS 12.

That doesn't necessarily mean that Apple is misrepresenting iOS 12's performance; we aren't privy to the exact conditions Apple tested under, and faster app load times ultimately mean faster keyboard loads anyway. But if you were hoping that iOS 12 might solve keyboard lag while bringing the keyboard up or while typing on it, it doesn't look like much has changed since iOS 11.

An argument against forced obsolescence

I’ve been testing iOS on old devices for six years, and I’ve never seen a release that has actually improved performance on old devices. At best, updates like iOS 6, iOS 9, and iOS 10 didn’t make things much worse; at worst, updates like iOS 7 and iOS 8 made old devices feel like old devices. Anyone using an older device can safely upgrade to iOS 12 without worrying about speed, and that’s a big deal. You’ll notice an improvement most of the time, even on newer devices (my iPad Air 2, which had started to feel its age running iOS 11, feels great with iOS 12).

Again, it’s not all rosy. We didn't notice any improvements in keyboard display times. You may still run into trouble running newer games, since there's no software update that can transform an old GPU into a new one. And the iPad Air and Mini 2, in particular, are going to continue feeling kind of slow in general—an iPhone-class processor and 1GB of RAM are just not enough power to keep a high-resolution tablet feeling snappy for five years. With devices as old as these, the condition of the battery can significantly affect performance, too. If you’ve never replaced your battery (or if it has been more than two or three years since you did it last), make an appointment with the Genius Bar before those $29 battery replacements go away at the end of 2018.

But if nothing else, iOS 12 is a convincing counterargument to the theory that Apple intentionally hobbles its old devices to force people to buy new ones. In addition to running more like iOS 10 did, it supports devices going all the way back to 2013, which sets a new record for iOS’ software support window. Given their age, these phones and tablets feel reasonably good in everyday real-world use, including browsing, emailing, and using most apps.