Galaxy S6 vs iPhone 6 vs One M9

We see whether Samsung's, Apple's or HTC's flagship smartphone is most deserving of your attention

Apple was the clear winner of 2014's battle of the smartphones in many buyers' minds, and the iPhone 6 was listed by several reviewers, including us here at V3, as the firm's finest handset to date.

By comparison, Samsung had a run of bad luck with the 2014 Galaxy S5, which failed to meet its sales projections. Equally, HTC's One M8, while critically praised, enjoyed only moderately good sales.

One year on, however, Samsung and HTC have returned to the smartphone battle ground, and once again attempted to dethrone Apple as ruler of the top-end market with their respective Galaxy S6 and One M9 smartphones.

Design and build
The iPhone 6 features a single-piece metal chassis with curved sides and a flat back, and was praised for its design when it was released in 2014.

Clearly aware of the popularity of the iPhone 6's design, Samsung has borrowed heavily from Apple in creating the Galaxy S6. Mixing elements of Apple's and Sony's designs, the Galaxy S6 has Gorilla Glass back and front faces and a metal frame that is almost identical in design to the iPhone 6's.

By comparison, the HTC One M9 has a close to identical design to its predecessor, the One M8, and features a rounded metal back that wraps round to the Gorilla Glass front, and 'Boom Sound' speakers. The only major design difference is that the One M9's sides are a different colour to its back and have a stepped front face.

HTC claims that the One M9's design combines the best elements of the One M7 and One M8, but we felt that it was actually a step backwards.

The stepped front aims to make it easier to get a solid grip on the handset. However, comparing it with the Galaxy S6 and iPhone 6, we found that the hard edge made the One M9 the least comfortable to hold.

This wasn't aided by the One M9's fatter 145x70x9.6mm measurements and 157g weight, which make it noticeably larger and heavier than the 143x71x6.8mm, 138g Galaxy S6 and 138x67x6.9mm, 129g iPhone 6.

The One M9 is also the least feature packed of the three and, unlike the Galaxy S6 and iPhone 6, doesn't feature a built-in fingerprint scanner.

Picking between the Galaxy S6 and iPhone 6 is more difficult. Overall, thanks to the use of metal, the design of the Galaxy S6 is a major step forward for Samsung and a definite improvement on past Galaxy handsets, which had flimsy-feeling polycarbonate frames.

The pebble shape of the Galaxy S6 also means it's every bit as comfortable to hold as the iPhone 6, which is one of the most ergonomically pleasing handsets we've experienced.

However, the fact that the S6 borrowed so heavily from Apple is difficult to ignore and means that, for originality alone, the round goes to the iPhone 6.

Winner: The iPhone 6

Next: Display and operating system

Galaxy S6 vs iPhone 6 vs One M9

We see whether Samsung's, Apple's or HTC's flagship smartphone is most deserving of your attention

Display
There's an ongoing argument among smartphone makers about the maximum pixel per inch density the human eye can detect.

At the bottom end, Apple traditionally argued that our eyes stop being able to spot differences in resolution once a screen breaks 300ppi and has loaded the iPhone 6 with a 4.7in 1334x750, 326 ppi Retina HD display.

At the top end, Samsung has been more optimistic about the human eye's potential and loaded the Galaxy S6 with a 5.1in, 2560x1440, 577ppi, Super Amoled touch screen.

Between the two, HTC has played it safe and loaded the One M9 with an equivalently specced 5in 1920x1080, 441 ppi, Super LCD3 screen to that seen on the One M8.

We're not going to lie when it comes to sharpness: we struggled to notice a marked difference in screen quality between the Galaxy S6, iPhone 6 and One M9 with everyday use.

However, with prolonged tests cycling through a variety of high-definition pictures and screen tests we did notice a disparity in quality between the three, and the Galaxy S6 is sharper.

Moving onto colour quality things get trickier. The One M9's colour levels, while still very good, were the weakest of the three and had a cooler, at times slightly washed out, look compared with the Galaxy S6 and iPhone 6.

Picking between the Galaxy S6 and iPhone 6 was more difficult as both displays have strengths and weaknesses.

The Galaxy S6 can display deeper blacks than the iPhone 6. This means that, in a number of circumstances, colours on the Galaxy S6 appear to have more 'pop' than those on the iPhone 6.

The Samsung phone's maximum brightness is also noticeably higher than the iPhone 6's.

However, whites on the iPhone are brighter to the point that, in some circumstances, they make it look like the Galaxy S6 is showing a very light shade of grey.

Overall, however, the iPhone 6's great colour calibration isn't enough to win the round from the Galaxy S6, which has a higher brightness and a sharper resolution.

Winner: The Galaxy S6

Operating system
The iPhone 6 runs the latest version of Apple's iOS 8, while the Galaxy S6 and HTC One M9 use customised versions of Android 5.0.2.

Traditionally, we've found it difficult to pick between Android and iOS as both have an impressive array of services and features, and the answer to which is better is determined largely by the user's wider technology ecosystem.

For example, those embedded in Apple's ecosystem will find it easier to set up an iPhone using an iCloud account, which also lets users sync data, files and even open web pages between iOS and Mac OS X devices. The Apple OS also comes with its own productivity services since the firm made key applications free, such as Pages and Keynote.

By comparison, Android offers an equally easy set-up process for people with Google accounts and lets users set new devices to mirror the settings of previous devices the user has logged into.

Android also comes with an equally impressive array of productivity services, such as Google Drive, Docs and Now.

However, the addition of custom skins changes things. We've never been big fans of Android skins as, even if they add useful services, they are a pain for general users and delay how quickly phones can be updated to new Android versions.

This is because the manufacturers have to tweak the skins' code to work with every new version of Android, a practice that can take months.

The problem is showcased by the Galaxy S6 and One M9, which are both yet to receive updates to Google's latest Android 5.1 version.

However, being fair to Samsung and HTC, the skins are not the worst we've seen and do at least add some useful features to Android.

Key positives for the Galaxy S6 include Smart Manager and multi-window support. Smart Manager lets users optimise performance by controlling which applications are using memory or battery power at any given time. Dual-screen support lets users have two apps open on the Galaxy S6 screen at the same time.

By comparison, HTC has loaded the One M9 with the useful Sense Home and BlinkFeed features.

Sense Home is designed to boost the One M9's BYOD appeal by adjusting the applications and services that appear on the home screen depending on the user's location. It can be configured for 'out', 'home' and 'work'.

BlinkFeed is a news aggregation service that uses information stored on the user's Google and social media accounts to push updates from various news outlets and contacts that it thinks will be of interest via a custom tiled interface.

Winner: The iPhone 6

Next: Security and performance

Galaxy S6 vs iPhone 6 vs One M9

We see whether Samsung's, Apple's or HTC's flagship smartphone is most deserving of your attention

Security
Apple fans have long held a false belief that using the firm's products makes them immune to hackers. This is, of course, a fiction, as demonstrated by the wave of Masque vulnerabilities being reported by FireEye particularly on jailbroken iOS devices.

However, it's fair to say that Apple's iOS platform has a definite edge on Android when it comes to security. This is largely because of the closed management policy Apple takes with iOS.

The policy blocks companies and individual developers tweaking iOS or selling applications without Apple's approval on the platform's official App Store.

Android, by comparison, takes an open approach and lets companies and developers adjust and alter the OS to their hearts' content.

This means that innovations can be brought to market faster on Android, and companies can change the software to work better in specific user cases, like Silent Circle did in creating its security and privacy focused Private OS.

However, the flip side is that it makes Android more susceptible to abusive behaviour, like trojan applications and malicious ad networks.

This is a key reason why the known number of Android threats is listed in the hundreds of thousands, if not millions, while the publicly disclosed iOS threats can be counted on one hand.

Picking between the two Android smartphones when it comes to security, the Galaxy S6 is the clear winner. Unlike HTC, which has chosen to rely on Android Lollipop's inbuilt security, Samsung has added a couple of innovative protection and management services to the Galaxy S6.

The best of these is Samsung's Knox security platform. Knox offers IT managers similar sandboxing powers to those on the BlackBerry Balance, allowing them to create separate encrypted work and personal areas on devices.

For businesses outside Google's ecosystem, Samsung has also announced a new custom Office 365 and Samsung Knox Business Pack for corporate devices that integrates Microsoft's cloud services directly into the management service.

Winner: The iPhone 6

Performance
When it comes to processors, the Galaxy S6, One M9 and iPhone 6 all use different chips. The Galaxy S6 runs a custom octa-core Exynos 7420 processor paired with 3GB RAM, while the One M9 uses an octa-core Qualcomm Snapdragon 810 processor and features 3GB RAM.

The iPhone 6 features an A8 chip with 64-bit architecture with M8 motion coprocessor and 1GB RAM.

Benchmarking the three phones using Sunspider and Basemark OS II, the Galaxy S6 had an overall lead on the iPhone 6 and One M9.

Geekbench tests integer, floating point and memory performance to create single-core and multi-core scores.

Sunspider uses JavaScript to run a number of browser-based tests several times to determine the speed of the browser and processor. Basemark OS II is an all-round benchmark that runs system, memory, graphics and web tests.

A higher score is better with Geekbench and Benchmark OS II, while a lower score is better with Sunspider.

The Galaxy S6 scored 1,474 single-core and 5,312 multi-core on Geekbench and 1,101.6ms on Sunspider. It also enjoyed 1,739 overall, 3,627 system, 1,309 memory, 2,481 graphics and 760 web scores on Basemark OS II.

The iPhone 6's A8 processor scored 1,619 single-core and 2,920 multi-core on Geekbench, 350ms on Sunspider, and 1,554 overall, 2,942 system, 784 memory, 2,339 graphics and 1,082 web Basemark OS II.

Finally, the One M9 scored 753 single-core and 2,935 multi-core on Geekbench, 1,640.5ms on Sunspider, and 1,288 overall, 1,407 system, 828 memory, 3,193 graphics, and 739 web on Basemark OS II.

With regular use we found the benchmarking differences negligible and all three handsets were lightning fast when faced with everyday tasks such as web browsing or document editing.

However, with prolonged use we noticed a few performance problems on the HTC One M9. Faced with ongoing demanding tasks, like video editing or 3D gaming, the One M9 can heat up to uncomfortable levels and begin to throttle performance.

Picking between the Samsung and Apple handsets, it's important to note that the Galaxy S6's processing lead will become important in the future as developers increase the resource demands of their applications to take advantage of improved hardware.

Winner: Galaxy S6

Next: Camera, battery, storage and price

Galaxy S6 vs iPhone 6 vs One M9

We see whether Samsung's, Apple's or HTC's flagship smartphone is most deserving of your attention

Camera
Apple, Samsung and HTC all made a big fuss about their respective smartphones' cameras when they unveiled the handsets. The One M9 is the winner on the megapixel front and comes with 20.7MP rear and 4MP Ultrapixel front cameras.

Taken on the One M9

By comparison the Galaxy S6 comes with a 16MP F-1.9 rear camera with optical image stabilisation (OIS) and a 5MP F-1.9 front-facing camera, and the iPhone 6 comes with an 8MP f/2.2 rear and 1.2MP front-facing camera.

However, as any photographer will tell you, picture quality is not necessarily determined by a camera's megapixel count and we found that the One M9's rear camera, while a step-up compared with HTC's One M8, is the worst of the bunch.

Photos taken on the One M9 are well above average for a smarthphone, but don't always appear as crisp as those taken on the iPhone 6 and Galaxy S6. We also found that the One M9's focus remains slightly hit and miss and struggled to capture moving images.

Taken on the iPhone 6

Photos taken on the Galaxy S6 and iPhone 6 were great, but the Samsung handset had a definite edge when it came to picture quality, particularly when shooting in low light.

Shots taken on the iPhone 6 in regular light, while decent, weren't quite as sharp as those taken on the Galaxy S6, especially when blown up. They could also on occasion appear slightly more 'noisy' and be prone to contrast and pixellation problems when used in low light.

Taken on the Galaxy S6

This is likely to be down to the custom F-1.9 lens and OIS on the Galaxy S6. Samsung claims that the lens lets in 60 percent more light than the Galaxy S5's lens which could well be true if our tests are anything to go by.

The Galaxy S6 was able to continue performing and shoot usable photos in lighting conditions that rendered the iPhone 6's rear camera all but useless.

Winner: The Galaxy S6

Battery
Battery testing the three phones by constantly looping a video file stored on the handsets, the Galaxy S6's 2,550mAh built-in lithium-ion battery lasted eight hours 30 minutes, while the iPhone 6's 1810mAh battery lasted eight hours and the One M9's Li-Po 2840mAh battery lasted seven hours and 40 minutes.

The tests rang true with real world use and the Galaxy S6 usually lasted two to three hours longer than the iPhone 6 and One M9 from one charge.

The Galaxy S6's lead is cemented by the inclusion of WPC and PMA wireless charging technology.

Winner: The Galaxy S6

Storage
The One M9 has the least internal storage options of the three at 32GB. Samsung currently offers 32GB, 64GB and 128GB versions of the Galaxy S6, while the iPhone 6 comes with 16GB, 64GB or 128GB.

However, it's worth noting that the One M9 is the only one of the three to feature a microSD card slot. This lets users add a further 2TB to the One M9's internal storage, meaning it can theoretically have a higher storage capacity than the iPhone 6 and Galaxy S6.

Winner: The One M9

Price
None of the three handsets is cheap, but the iPhone 6 carries the lowest upfront cost at £540 for the basic 16GB version. The One M9 currently costs £580 SIM-free, while the basic 32GB Galaxy S6 costs £600.

Winner: The iPhone 6

Next: Overall winner

Galaxy S6 vs iPhone 6 vs One M9

We see whether Samsung's, Apple's or HTC's flagship smartphone is most deserving of your attention

Overall winner: The Galaxy S6

Having picked up just one round, the HTC One M9 is the loser of this head to head review. The Galaxy S6 and iPhone 6 won four rounds each, but for us the Samsung handset has a definite edge.

Featuring a superior display and better camera, battery and general performance the Galaxy S6 is currently the best smartphone out there.

However, with the future-proof assurances offered by Apple regarding the iPhone 6 software, whether the Galaxy S6 maintains its lead will be determined by how fast Samsung manages to roll out software updates to the handset.