It's nearly time for Samsung to unveil the next iteration of its flagship smartphone. Coming off a shaky 2014, the South Korean company has some work ahead of it to prove it's still the king of smartphones.
The Galaxy S6 marks a critical moment in the history of the world's largest smartphone maker. With profits down and sales of the Galaxy S5 lacklustre, we'll soon see whether Samsung has taken heed of criticisms over the design of its flagship product and can offer a response not just to Apple's iPhone 6 and iPhone 6 Plus, but to devices from Lenovo, Huawei, and Xiaomi which are affecting the company's sales in China.
Samsung unveiled the Galaxy S5 at last February's Mobile World Congress (MWC) event and kicked off its post-launch marketing just days later with its usual bravado, boasting the S5 was selling "faster than the Galaxy S4 so far".
Indeed, Galaxy S5 sales exceeded the Galaxy S4's first month sales by one million to reach 11 million, but as the Wall Street Journal reported in November, the company only sold 12 million in the first three months - four million fewer than the Galaxy S4 over a similar period. While sales were up in the US, in China they were 50 percent lower than the S4, the paper reported.
Samsung has had a year to rethink its strategy for the Galaxy S6 and several months to develop a response to Apple's iPhone 6 and iPhone 6 Plus - not to mention Apple Pay, Apple Health, the forthcoming Apple Watch, and Apple's new partnership with IBM.
As in previous years, Samsung is likely to twin its new flagship launch with announcements around its own enterprise efforts like Knox, the software which informed some of the security enterprise features Google introduced with Android Lollipop.
While it took a conservative approach to styling with the Galaxy S5, Samsung last year experimented with bolder designs on several devices, which may indicate what's in store with the Galaxy S6.
The Galaxy S6 display
Samsung this year released its first curved screen device, the Galaxy Note Edge, which shifted the display and right hand bezel to the edge of the device.
While Samsung believes that changes to the display may keep it ahead of rivals, the case for bringing Edge styling across to the S6 isn't clear. It certainly would let the device stand out against the iPhone 6. As per recent rumours, a special curved edge edition of the device may become part of a multi-pronged Galaxy S6 response to the iPhone 6 and iPhone 6 Plus.
The Galaxy S5's 5.1-inch full HD Super AMOLED display offered a resolution of 1,920 x 1,080 pixels with a pixel density of 432ppi.
Times have moved on since the release of the S5, and LG's ratcheted up the specs with a Quad HD display with a 2560 x 1440 pixel resolution for its own flagship, the G3. Samsung is likely to at least offer something on par with that device with the S6. The S6 could well bear a resemblance to the Note 4, which came with its 5.7-inch Quad HD Super AMOLED screen with a 2560 x 1440 pixel resolution (518 ppi). Supposed leaked benchmarks of a Samsung device that fits the profile of a flagship phone indicate it will have 5.5-inch display.
Will the Galaxy S6 go full metal?
Whether Samsung's next flagship device will sport a metal case is one of the niggling issues for Samsung, yet the company has stuck to plastic thus far. Besides keeping the device light, Apple's iPhone 6 bendgate drama showed there are good reasons for using plastic on large- screen devices.
However, Samsung's mid-range Galaxy A series ushered in full metal unibody designs with the A3, A5, and now the A7. They all achieve a higher quality look and feel that might be welcome by fans of the Galaxy S5.
And following the lukewarm reception to the Galaxy S5, the company has experimented with new designs, such as the chamfered edges on the Galaxy Alpha and the Galaxy Note 4/Note Edge duo, which could well show up on the S6 too.
Phone or phablet?
Apple silenced critics by releasing the 5.5-inch display iPhone 6, yet still managed to keep the devices light and, by shaving 0.7mm of the iPhone 5S' thickness, reasonably easy to hold.
A key question is whether the Samsung Galaxy S6 will be more smartphone or phablet, and how slim it will be.
As it is, with a 5.1-inch display diagonally, the Galaxy S5's dimensions are 142mm x 72.5mm x 8.1 mm, and it weighs 145g.
The 5.7-inch display Galaxy Note 4's measures 153.5mm x 78.6mm x 8.5mm, and weighs 176g while the 5.6-inch Galaxy Edge lands at 151.4 x 82.3 x 8.4 mm, and weighs 174g.
These compare to the iPhone 6's dimensions of 138.1mm x 67mm x 6.9mm and 129g.
Besides introducing metal, a major focus for Samsung in its A-series and Alpha phones has been their thickness, which again may provide a clue as to where Samsung may be headed with the S6.
The latest Galaxy A7 is just 6.3mm thick, a whisker thinner than Apple's iPhone 6, and thinner than its A5 and A3 cousins, which are 6.7mm and 6.9mm deep respectively.
Expect a selfie makeover
The Galaxy S5 shipped with a 16-megapixel rear camera and just a two-megapixel front camera with wide angle shots. The S5 arrived at the height of the selfie craze and since then phone manufacturers have moved wholesale to better front-facing cameras.
Thus it's reasonable to expect the Galaxy S6 to have at the very least a five-megapixel camera on the front with all of Samsung's selfie software features such as Ultra Wide Shot and Auto Selfie modes. Rumours indicate that the Galaxy S6's front camera will have a 20-megapixel sensor.
You've got sensors, now what to do with them
One of the standout features that Samsung introduced with the Galaxy S5 was its fingerprint reader. While the company announced a partnership with PayPal to use it for payment authorisation, the feature hasn't generated the early momentum that Apple has with Apple Pay.
Samsung will almost certainly carry the fingerprint reading technology over from the S5 to the S6. The company may also be brewing a bigger response to Apple Pay and Touch ID signed payments via a partnership with LoopPay to create a mobile wallet system.
Last year's Galaxy S5 launched with a heart rate sensor which didn't seem particularly useful but fitted with the health theme found in many of its wearables. Samsung has kept the heart rate monitor for subsequently released devices including the Note 4, so it could be expected it will do it again for the S6.
Other core specs
The Galaxy S5's lineup of core features included LTE Cat 4 (150Mbps download, 50Mbps upload), a 2.5GHz quadcore application processor, TouchWiz based on Android KitKat, 2GB of RAM, either 16GB or 32GB of onboard storage, and microSD storage expandable up to 128GB.
Clearly, Samsung will be beefing up all these features. Those feeding the rumour mills believe it will use an Exynos 7420 64-bit octacore CPU, 3GB of RAM, and 32GB of storage.
Given the larger screen and faster processors, Samsung could also be expected to boost the battery from the S5's 2800mAh capacity unit to something closer to the Note Edge's 3000mAh one.
TouchWiz: Less is more
Samsung had already scaled back TouchWiz in the Galaxy S5, and is likely to do the same with the Galaxy S6, following its efforts to remove bloatware and duplicate services from the Galaxy Note 4.
Indeed, a recent report from Business Korea claimed that Samsung is aiming to bring TouchWiz on the S6 up to par with the performance of stock Android on the Nexus 6.
Wearables with the phone
Samsung has already had a bash at wrist-worn wearables with the Gear S running Android Wear but so far its efforts haven't set the world on fire - and have drawn comparisons to a miniaturised smartphone that looks oddly large on a wrist.
With Apple Watch looming, Samsung has yet another chance to improve its formula, possibly borrowing a few ideas from Apple.
According to Samsung specialist site Sammobile, Samsung looks to be doing just that with a round watch codenamed Orbis, which is slated for release at MWC.
The device is tipped to have a crown-shaped power button a la the Apple Watch's 'Digital Crown' and a rotating bezel on top. While the crown is the centre piece of Apple Watch's functionality, the bezel is expected to serve that role on the Orbis. And like Apple Watch, Orbis has been given a high-end appearance.
The question is whether Samsung will be able to achieve the same level of integration Apple is planning around health, payments, and messaging.
Samsung picked MWC in Barcelona to launch the Galaxy S5 last February but that doesn't mean 2015 will see a repeat of this, even though the vendor should certainly be expected to attend the event. Samsung traditionally occupies the largest space at MWC and will no doubt flex its marketing muscle again there this year.
In 2012, Samsung launched the Galaxy S3 at its own event in London on 3 May, while the Galaxy S4 was released at a Samsung event in New York on 15 March the following year.
Samsung has gradually brought its release schedule forward over the past few years but is yet to go earlier than February for a flagship, despite rumours it would unveil Galaxy S6 at the January CES conference in Las Vegas.
This year's three day MWC event starts on 2 March, so it wouldn't be surprising to see an announcement around that time.
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