Apple iMac 21-inch review (late-2015): A little computer with a LOT of pixels

Apple 21.5-inch iMac (2015) review: Design

Visually, though, the iMac hasn’t changed a jot. It’s still a drop-dead gorgeous, and pleasingly compact, all-in-one PC, and even if the screen’s bezels are beginning to look a bit on the chunky side, the design alchemy of metal, glass and perfectly-tailored curves still looks great from any angle. There aren’t many PCs I’d want to see the back of, but the iMac is one of them. It’s so pretty, in fact, that it almost seems a shame to plug in any cables at all.

On that note, you may be seeing more of the iMac’s rear than you want to. All the ports – the four USB 3, two Thunderbolt 2, Gigabit Ethernet, SD card and headphone jack – are located at the back. And unless you want to run the risk of gouging the iMac’s perfect metallic hide by blindly trying to insert a USB flash drive, you’ll have to get up and twist the iMac around every time you want to plug something in. It may be annoying enough to make you rush out and buy a USB 3 hub. 

Still, the arrival of super-fast Thunderbolt 2 ports goes a little way towards making amends, and the wireless side of things is well-covered: 802.11ac Wi-Fi and Bluetooth 4.1 are enough to cheer anyone up.

What’s more, the 21.5in iMac now comes with Apple’s upgraded set of Magic accessories. The Magic Keyboard 2 and Magic Mouse 2 are supplied as standard, and you can swap the mouse for a Magic Trackpad 2 for £44, or have both for £109. If you want to find out more about what I think of Apple’s magical new accessories, then you can read what I wrote in my 27-inch iMac with Retina 5K display review. In short, they’re very nice. I like them, mostly, and you probably will too.

Apple 21.5-inch iMac (2015) review: Full HD display

If you’re considering buying one of the cheaper 21.5in iMacs, I have one essential piece of advice: do not under any circumstances look at any Retina iMacs or MacBooks before spending your cash. If they’re nearby, close your eyes and walk straight past. This is very, very important. If you so much as peek at a Retina display, the standard 21.5in iMac will look utterly, utterly mediocre by comparison; all crude, obvious pixels and jagged, stair-stepped text. Trust me, you get used to the sharpness of Retina displays near-instantaneously, and when you go back to a normal display – well, it looks pretty rubbish.

Still, by the standards of Full HD displays, the iMac’s 21.5in screen is really very good. The bright, high-contrast IPS panel does a terrific job with everything from movies and photographs; the panel produces all the colours most people would ever want it to; and it’s accurate, too, so whatever’s onscreen looks exactly how it should. And in all fairness, if you’re used to using a larger 23in or 24in Full HD monitor, the 21.5in iMac will actually look a little sharper, as the pixels are crammed into a smaller space. Just don’t look at the Retina 4K iMac – or you will have to buy that instead.

Apple 21.5-inch iMac (2015) review: Retina 4K display

Trust me on this, the Retina 4K screen really is something special. The iMac’s 4,096 x 2,304 resolution serves up 14% more pixels than most 4K monitors, and this means only one thing: images are outrageously sharp. Crystal clear is an understatement.

I’d even go as far as to say it was a better all-round display than that of the 27-inch Retina 5K display. Why? Simple. It’s only an imperceptible sliver less colour accurate according to our X-Rite colorimeter (the average DeltaE is 1.1, if that means anything to you), but it’s every bit as bright (446cd/m2), reproduces the same range of colour (86.5% of the Adobe RGB gamut), and the contrast ratio of 1,247:1 is astonishingly good. 

So, why is it better? Because the backlighting is far, far more even than its larger 5K sibling, which means that colours are far more even and uniform across the panel. Where the 27-inch iMac suffers due to a backlight which varies in intensity by as much as 15% as you look across the display, the 21.5-inch iMac is much more even-handed, varying by no more than 7%. For designers and visual artists who need to know that what’s onscreen is faithful, this is an important distinction.