The Samsung Galaxy S9 could be announced in just a couple of months - as early as January's CES 2018, according to VentureBeat - but how do you go about making the best phone even better?

A performance boost is traditionally found on Samsung's list, even if one is not particularly required, and in 2018 we'll see the Galaxy S9 sporting either the Snapdragon 845 (in the UK) or the newly announced Exynos 9810 (elsewhere). While the Snapdragon 845 is thought to be a 7nm chip, the Exynos 9810 uses the second-generation 10nm process.

As in previous iterations, we expect there will be two versions of the S9: a standard model with a 5.8in display, and a Plus model with a slightly larger 6.2in screen. Both will feature the dual-curved edge and Infinity display, but sadly the new in-display fingerprint-scanning tech originally rumoured for the Galaxy S8 is now looking unlikely for the Galaxy S9. However, they may still feature higher-capacity batteries (enabled by a new type of motherboard).

We would be amazed if they didn't also get the Note 8's dual-camera, which combines two 12Mp telephoto and wide-angle lenses, both with OIS.

We don't think the design will change much, but there are reports that the Galaxy S9 could have a modular design - not that this turned out so great for the LG G5. Samsung is allegedly planning to introduce magnetic pins on the back of the phone that will allow the attachment of external modules. Until we hear more on that front we'll take it with a pinch of salt.

Features were standardised across the line with the Galaxy S8 and S8+, so expect only minimal differences in those specifications affected by the larger screen, such as battery capacity (a larger case allows for a little more juice), dimensions and weight. As such, the rumours you read in this article will be applicable to either handset.

(Also see our Samsung Galaxy S8 and Galaxy S8+ reviews, and rumours of a Galaxy S9 Mini.)

When is the Galaxy S9 release date?

Expected release date: January 2018 announcement, mid-February onsale

Speculating over Samsung Galaxy release dates used to be easy, with the S series unveiled during an Unpacked press conference a day ahead of MWC, traditionally held in late February or early March, and the Note series in a second Unpacked conference the day before IFA at the beginning of September. If that were still the case we'd expect to see the Galaxy S9 announced on Sunday 25 February 2018.

However, in 2017 it announced the Galaxy S8 and S8+ in March, some time after February’s MWC tradeshow. The phones eventually went on sale at the end of April. 

And now that it has broken that tradition, rumours are flooding in that the Galaxy S9 will appear even earlier in 2018, rather than later. Samsung display will start shipping OLED panels for the phone two months early in November, and the Galaxy S9 has already been spotted on Geekbench (in July).

All this is potentially leading up to a January announcement, with a mid-February onsale date. And that could be a good idea for Samsung, which will want to claw back sales from Apple's brand-new iPhone 8 and iPhone X.

VentureBeat sources claim the phones will be on show at CES 2018.

How much will the Galaxy S9 cost in the UK?

The Galaxy S8 and S8+ were Samsung’s most expensive S-series phones yet at £689 and £779 respectively. Part of this extra cost can be attributed to the new features, but finances following both Brexit and the Note 7 disaster have almost certainly come into play here, too.

Until this year, Samsung always kept its pricing reasonably constant, and in line with other flagship phone makers. For that reason we’d be surprised to see the price go any higher than the current RRP.

It’s always worth considering with Samsung phones that - more so than with any other manufacturer’s smartphones - SIM-free prices fall rapidly in the few months following launch.

What are the rumoured new features and specifications of the Galaxy S9?

Samsung reportedly began working on the Galaxy S9 in late March 2017, which would mean it is already six months ahead of schedule compared to where it was with the Galaxy S8 and S8+ last year.  And that means more time for quality control, more time for building in new features and, hopefully, more happy customers.

Amazingly, in July 2017 an early version of the alleged Galaxy S9 was spotted in the Geekbench database - that's some seven or eight months before we expect to see the phone announcement. A device with the model name SM-G9650 is listed with a 1.78GHz quad-core Snapdragon 845 processor and just 4GB of RAM. It scored 7371 points in the RenderScript test, which is lower than the Galaxy S8 managed in the same test. There are no performance scores.

Rumoured specifications Samsung Galaxy S9 Samsung Galaxy S9+
Price £689 £779
Operating system Android O 8.0 with TouchWiz Android O 8.0 with TouchWiz
Processor Qualcomm Snapdragon 845 (Exynos 9810 UK) Qualcomm Snapdragon 845 (Exynos 9810 UK)
GPU Adreno 550 Adreno 550
RAM 6GB LPDDR4 6GB LPDDR4
Storage 64GB with microSD support 64GB with microSD support
Display 5.8in (2960x1440, 570ppi, 18.5:9) Super AMOLED 6.2in (2960x1440, 529ppi, 18.5:9) Super AMOLED
Fingerprint scanner Yes Yes
Ports USB-C USB-C
Audio Stereo speakers Stereo speakers
Camera 12Mp dual-camera, dual-OIS 12Mp dual-camera, dual-OIS
Battery Circa-3000mAh, Adaptive Fast Charging (wired & wireless) Circa-3500mAh, Adaptive Fast Charging (wired & wireless)
Waterproofing IP68 IP68
Extra features Heart-rate sensor, Bixby AI Heart-rate sensor, Bixby AI

Display

An unnamed source suggests the first work on the Galaxy S9 began with the screen, and that there is not expected to be any change with the sizing: so we’ll see a 5.8in Galaxy S9 and 6.2in Galaxy S9+.

The Bell reports that Samsung has already ordered these screens from suppliers, but with one key difference: they will feature the in-display fingerprint-scanning tech that was rumoured for but never made it into the final spec of the Galaxy S8.

As we approach the Galaxy S9 release date, however, that's looking increasingly unlikely. The Investor reports that the in-display fingerprint-scanning tech won't be ready in time, while Ice Universe says the fingerprint scanner will remain on the rear but under the camera rather than to its side.

We’d expect to see the same 2960x1440, 570ppi, Super AMOLED ‘Infinity’ panel on the S9, and another 529ppi panel on the S9+. Given that Samsung by default limits the screen resolution to Full-HD+ (2220x1080) in the Galaxy S8, we really don’t think it will push up the resolution up to 4K.

It is possible that despite keeping the same dimensions and resolution the display technology itself could be improved. Samsung is reportedly using screen tech codenamed ‘Sunflower’ for the Galaxy S9 - it’s still Super AMOLED, but should improve display fidelity and be more consistent and reliable.

The new virtually full-screen 18.5:9 ratio will also likely remain, as will features such as the always-on display and edge functionality. However, in 2018 we could see Samsung follow the route Apple has taken with the iPhone X and minimise the top bezel even further.

Rather than a thin strip at the top in which to house the sensors, camera and speakers the iPhone 8 features a notch at the top and then minimises the bezels to the left and right of this. It's not an attractive design, but it does allow for a higher screen-to-body ratio. Patents unearthed by Galaxy Club suggest Samsung has the same idea.

Samsung will allegedly implement its Y-OCTA tech into both models this time around, with only the standard Galaxy S8 getting the treatment in 2017 (the Galaxy S8 Plus does not and the Note 8 apparently will not get it either). Y-OCTA uses a single manufacturing process for the screen and the touch-film element.

In 2016 Samsung patented a glass-coating technology that helps water to bounce off the screen, making it much easier to use in the rain. This tech could well be introduced in the Galaxy S9, which will itself most likely be waterproof. (The Galaxy S8 is rated IP68, which means it is resistant to submersion up to a depth of 1.5m for up to 30 minutes.)

Processor

In the UK we'll almost certainly see the Qualcomm Snapdragon 845 powering the Galaxy S9, which is on track for an announcement in early December. It may once again hold the exclusive on this chip, forcing rivals to wait until the Galaxy S9 has been unveiled to use that same chip, but for now that is merely a rumour.

The 10nm Snapdragon 835 Samsung helped Qualcomm to manufacture was 27 percent faster and 40 percent more energy-efficient than the company’s previous 14nm chips. The upcoming Snapdragon 845 is said to be built on the 7nm manufacturing process, and will be even faster and more efficient than ever.

(The nm figure relates to the distance between transistors, and the more you can squeeze on to a chip the faster it will be.)

Elsewhere in the world Samsung uses its own Exynos chips, and has just announced the Exynos 9810 which is the most likely candidate. 

We don't know a great deal about the 9810, but we do know it's built on the second-generation 10nm process, which is interesting given that the Snapdragon is thought to be 7nm. We also know that it features M3 cores, and builds in improvements to the GPU, which may now be the Mali-G72. 

Samsung has announced that its next-gen Exynos chips will feature LTE modems that support six carrier aggregation (6CA). A first in the industry, Samsung says this unlocks a max download speed of 1.2 gigabits per second (20 percent faster than the Galaxy S8, which has a 5CA modem). It should allow you to download an HD movie in just 10 seconds, and eliminate buffering.

Samsung is also said to be looking to build AI processing right into its chips, which will perform better when hard-coded to the chip than left to the software. So Bixby could become a lot more efficient.

Storage and RAM

You get 64GB of storage as standard with the Galaxy S8, along with microSD support. That’s already quite generous, so we’re not expecting to see any changes here.

Something we might see in the Galaxy S9, though, is for Samsung to finally push up the RAM allocation from 4GB to 6GB, as it has done for the Note 8. This is by no means out of the question, with some phones that are now a year old offering this amount of memory. It would also help it in its quest for ever-increasing performance.

Battery

Although the size of the phone is not expected to change, we could see battery capacity get a boost with the Samsung Galaxy S9. ET News reports that Samsung will facilitate this using a new type of motherboard that uses substrate-like PCB technology to squeeze in more layers of components - or extra room for the battery pack.

Fast charging - both wired and wireless - will likely feature, though we suspect Samsung will continue to use its own Adaptive Fast Charging tech rather than the Quick Charge built into Snapdragon processors.

Camera

Samsung traditionally leads the pack when it comes to new smartphone features, so we’re somewhat puzzled by the fact it has yet to introduce a dual-camera. Nevertheless, one has been confirmed for the Note 8, so expect it to feature in the Galaxy S9 too.

Samsung’s Note 8 has a 12Mp dual-lens camera with dual-OIS and 2x optical zoom. CAD drawings suggest it could be a virtical array like the iPhone X.

It's been claimed that the Galaxy S9 will be able to shoot incredible 1000fps slow-mo video. This will apparently be achieved using a three-layered image sensor that adds DRAM to the sensor and logic chip, and of which it will begin mass production of in November. This builds on the two-layered approach seen in current high-end smartphones, though Sony has also used a three-layer system in its XZ Premium and XZ1 phones.

Ports and connections

Samsung introduced USB-C rather than Micro-USB for the Galaxy S8, though it didn’t follow the likes of Apple in removing the 3.5mm headphone jack and relying on wireless or USB-C audio. There is a danger it could take that plunge this time around, though nothing has yet been confirmed.

Fingerprint scanner

One change we would like to see in the design, and something we hope Samsung will take into account following significant consumer criticism, is the awkward placing of the rear fingerprint scanner. It’s not so much being on the back of the handset that offends us, but how it is wedged in beside the camera as if it were an afterthought.

The Galaxy S9 could be the phone in which we finally see the fingerprint scanner built into the screen glass itself. Qualcomm has announced Qualcomm Fingerprint Sensors, a new ultrasonic technology that allows fingerprint-sensing tech to be built directly into a phone’s OLED screen. It also works in glass and aluminium.

Less revolutionary alternatives might include the scanner taking a more central position below the primary camera, or Samsung taking a leaf out of Sony’s book by building it into the power button on the edge. Or maybe Samsung will go all in with iris scanning. To be fair, any of these options would be preferable to what we have now.

Audio

The audio on a phone can be a bit forgotten but Samsung won't with the Galaxy S9. According to rumours it will not only keep the headphone jack but also come with wireless AKG headphones in the box. They might just be tuned by AKG like the current Galaxy phones but it still sounds good.

Software

We’re expecting the final version of Android O to be revealed in September or October 2017, with the next version - Android P - not due until the same time next year, well after the Galaxy S8’s anticipated announcement. It’s therefore almost certainly the OS you’ll find onboard the S9 and S9+, albeit with the TouchWiz UI on top.

Samsung also introduced the Bixby AI assistant in the Galaxy S8, which we would have thought would have only got more intelligent for the Galaxy S9.

Design

It is way too early for leaked images of the Galaxy S9 and S9+ (the main image shown on this article is of the Galaxy S8 Plus), though we will publish them here as soon as we spot them.

Read next: Best new phones coming in 2017 and 2018

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