Introduction
Some phones just can't be reviewed in a vacuum, the competition between them is so fierce - and their price tags so high - that they have to be compared against each other under a microscope to determine the best one for you. The Apple iPhone 6s and Samsung Galaxy S6 are joined by the Sony Xperia Z5 for this three-way fight.
The iPhone 6s and Galaxy S6 have the biggest mindshare amongst consumers and will report back the biggest sales. The Xperia Z5 doesn't enjoy the marketing budget of those two, but is well-known by people interested in smartphones.
We'll put the trio through various tests, covering all major functions. Armed with that info, you can pick the winner based on the categories that are most important to your daily routine.
Before we delve into the nitty-gritty, let's do quick introductions for each phone.
The Apple iPhone 6s is almost like the gold standard for smartphones. A phone can have a better camera than the 6s or a worse camera, last longer on a charge or shorter, it's what many people use it as the yardstick. And with good reason - how many of you don't know at least one person with an iPhone? You've seen it, you've played with it, you probably know its strengths and weaknesses.
Android answered Apple's challenge for specs superiority (issued with the iPhone 4) and indeed Samsung made it its guiding design principle for several years. With the Galaxy S6 it finally admitted that design matters too. Samsung's manufacturing capacity and rich profits allowed it to splurge for the best hardware on the market. But has it nailed the ethereal "x-factor" that makes the iPhone transcend its spec numbers?
Sony's breakneck "two flagships a year" pace was either going to wear out the company - and the patience of its customers - or it was going to result in the best phone ever. Due to the short schedule, new Xperia Z releases seem to bring only marginal updates. Still, we're comparing against the iPhone and the Galaxy, not against the Z3 or Z4.
Hardware
We have a mix of metal and glass for the exterior of the three. The Apple iPhone 6s is mostly metal (the sides and the whole back), using glass only for the front. Apple dropped Gorilla Glass (even though the Cupertino company is responsible for popularizing it) and went with Ion-strengthened glass.
The metal is 7000-series aluminum and has smooth, round sides and corners. The new material is slightly denser though the majority of the added weight seems to come from the 3D Touch display. Its glass has beveled edges, creating one smooth curve that goes from glass to metal.
The Apple iPhone 6s is shrouded entirely in aluminum and glass
The Samsung Galaxy S6 has a metal frame, which is exposed on the sides, and Gorilla Glass 4 on the front and back. The two glass panels have a slight bevel on their side, but the transition isn't as smooth as on the iPhone. The metal sides are squared off too so that the side buttons do not sink into the body of the phone.
The Galaxy S6 is the thinnest and lightest of the bunch - 6.9mm and 138g. The camera module sticks out the back though. It doesn't affect handling and it's centered, so it doesn't cause the phone to wobble like the iPhone's camera.
The Galaxy S6 is more glass than metal
The Sony Xperia Z5 is all 90°. The metal frame makes up the sides of the handset while scratch-resistant glass covers the front and a unique matte glass covers the back. Both panes of glass sink into the metal frame, so you feel a sharp metal edge as you swipe from the side. This will keep the glass a hair off the surface the phone is lying on though, which will reduce the scratches a bit.
The Xperia Z5 is the thickest and heaviest of the three - 7.3mm and 154g. It has the biggest battery and features waterproofing, which is more than a fair trade off for the bigger digits. Also, the camera is flush with the back.
The Xperia Z5 also has glass on the back, but the frosting effect is unique
The three phones project a different image. The iPhone 6s is smooth and inviting, the Xperia Z5 has an aggressive, angular look, while the Galaxy S6 sits somewhere in between.
Angles aside, the Sony Xperia Z5 has the most extensive tooling. It starts with the stereo speakers on the front (the other two have just one speaker), an easily accessible card slot, then there's a dedicated shutter key and a lanyard eyelet (which most other phones have abandoned).
It's subtle but you can feel Xperia's adventurous nature. You can secure the phone with a strap, take photos even when the screen is wet, store plenty of photos and videos on the microSD card, even the battery will last a long, long while. And if you're starting a campfire party, you have a couple of good speakers available.
The Galaxy S6, Xperia Z5 and iPhone 6s side by side
The Samsung Galaxy S6 is a jetsetter. Gone is the rugged exterior of the S5, the S6 is all business on the outside. It matches your office building with a metal and glass exterior, the glass requires upkeep (wiping the fingerprints) like your tie requires straightening. The heart rate and blood oxygen sensors give you a read on your health, since diet and exercise is such a hot topic. If only the IR blaster could advance the slides of your PowerPoint presentation.
The Apple iPhone 6s is more solitary. It has a hardware Mute switch, so you can always make sure you're not disturbed. It's also the only one of the three that doesn't have a dual-SIM version. It lives up to its household name with a masterful build, without being flashy.
The iPhone and the Galaxy share a number of design decisions like putting both the USB port and the audio jack on the bottom, the loudspeaker too. The Xperia stands apart and puts its speakers up front, the audio jack on top.
Winner: Sony Xperia Z5. We can't judge aesthetics since those are purely subjective. In objective terms, the Xperia Z5 is the most practical with a waterproof body and expandable storage (we'll look at the screen and battery separately). A camera that doesn't protrude helps too.
Runner-up: Apple iPhone 6s. The only phone with an all-metal unibody here, indeed one of the few such smartphones in general.
While it may be one of Samsung's most beautiful devices, the Galaxy S6 has a couple of rough edges - the glass on the back gets smudgy quickly (Xperia's frosted glass handles it better) and the camera sticks out a good deal out the back. The Galaxy S6 edge has a lot more wow factor and would have topped the iPhone.
Screen
There's been plenty of debate about the ideal screen size and resolution and even Apple changed its mind, despite having the strongest convictions on the matter. The iPhone 6s is below the average size for an Android at 4.7" and the resolution is a result of a fixed pixel density (Retina's 326ppi).
Samsung and Sony settled on almost the same screen size, 5.1" and 5.2" respectively, but you need to keep in mind that the Xperia uses part of its screen for on-screen buttons. Android is a lot more flexible about resolution than iOS, so each maker has their own considerations about the resolution they picked.
Samsung uses its in-house Super AMOLED, which was perfected over several generations. It has market-leading color accuracy and perfect black levels for a high-contrast image that pops. These displays use a different matrix arrangement though, which benefits from a higher pixel density. Then there are the bragging rights, of course.
Both Apple and Sony use IPS LCDs, the standard if you want good viewing angles, though both have additional features to improve the image quality.
The Samsung Galaxy S6 screen is both the dimmest and brightest of the three here. The difference comes from the setting - manual control gives you a maximum of around 470 nits, but if you leave the phone to manage the brightness it can go as high as 750 nits when needed.
The Sony Xperia Z5 and Apple iPhone 6s have roughly similar max brightness (the Z5 is mildly brighter on auto, 600nits). The Xperia, however, disappoints with its poor contrast, under 1,000:1, which is common among mid-range phones but not okay for a flagship. Sony's improved Contrast filter that's part of the display assembly is responsible for deeper blacks than before but it didn't improve much about the contrast ratio.
The Apple iPhone 6 goes up to nearly 1,500:1. You need to be in a dark room to really see the higher contrast (theoretically infinite, but limited by reflections) of the Galaxy S6.
The Galaxy S6 brightness slider is fairly honest, but the other two do not affect brightness linearly. The Xperia is the worst offender here, giving you just 90nits out of a maximum of close to 600nits at mid position. This may sound like nitpicking, but it means you don't have fine control over brightness - the first half of the slider handles a 90nit range, the second half handles nearly a 500nit range.
Samsung's Super AMOLED displays are built to keep reflectivity low. Even on a bright sunny day the Galaxy S6 screen remains legible, it's one of the very best we've seen in this category. And that's on manual! The Apple iPhone 6s also is a great performer, but Xperia Z5's poor contrast makes it pretty average.
The Samsung Galaxy S6 has several screen modes - one that aims for perfect accuracy and others that create a punchier image to various degrees. They boost saturation and contrast, which can look great for photos and in the general UI, but can annoy purists. Luckily, everyone can pick the mode they like best.
The Xperia Z5 screen scores above average in color accuracy, however the white balance is off with a purplish tint. Turning on X Reality and other image enhancement options makes the color accuracy a bit worse and reduces the max brightness slightly. You can fine tune the color rendering using the Red, Green and Blue sliders, but it's not an easy thing to do and the UI does little to help.
The Apple iPhone 6s has more accurate colors than the Z5, average deltaE of 3.6 compared to 6.6. The white has a slight blue tint, also the red channel deviates more notably, but either way, it's one impressively tuned screen out of the gate.
Winner: Samsung Galaxy S6. It's the sharpest screen with the best contrast and sunlight legibility on the market, it's got perfect color rendering as well. And in Auto mode it can be brighter than the other two when needed.
Runner-up: Apple iPhone 6s. We wish Apple would offer more screen size variety than just 4.7" and 5.5", but in terms of image quality the iPhone 6s display is more accurate and with better contrast than the Xperia. Outside it's almost as legible as the Galaxy too.
Sony actually took a step back in contrast, the Z3+ did better than the Xperia Z5. Sure, the 5.2" 1080p screen is bigger and sharper than the iPhone, but it's not on par with it in the other tested areas.
