The Samsung Galaxy S8 and S8+ only hit shelves a few months ago but that doesn't stop speculation for their successors. As is always the way, as soon as one great device appears, there are always those wanting more. 

Here are all the rumours relating to what we assume will be called the Samsung Galaxy S9 and S9+ when they launch, though apparently codenamed "Star" for now. We've also thrown in a few things we'd like to see too so feel free to do the same in the comments.

  • Not expected until March or April 2018
  • Samsung Galaxy Note 8 will likely appear first

The Samsung Galaxy S8 and S8+ were officially announced on 29 March, with general availability starting on 28 April so we aren't expecting to see the S9 and S9+ before March or April 2018. Sammobile has reported that there will be two models again this year and their model numbers are known as SM-G960 for the S9 and SM-G965 for the S9+.

The South Korean company's latest device is the Galaxy Note 8, which was unveiled on 23 August so take a look at our round up on that device as there are likely to be a few hints as to what features we might be able to expect to see appear on the S9 and S9+.

  • Huge design changes not expected from S8 and S8+
  • All-screen front likely to remain 
  • Fingerprint sensor built into display reported and disputed

As we are still relatively hot on the heels of the Galaxy S8 and S8+, rumours are thin on the ground for the Galaxy S9 and S9+ at the moment. We're expecting that to change now that the Note 8 has launched though so keep your eyes peeled from now onwards.

We're not expecting huge changes in the design from the Galaxy S8 to the S9, with more subtle differences more likely like the company did from the Galaxy S6 to the S7, rather than the S5 to the S6 and the S7 to the S8.

That almost all-screen front will therefore no doubt remain a key design detail, along with the dual edges, though we wouldn't be surprised to see the rear-mounted fingerprint sensor move elsewhere. The placement of the fingerprint sensor has been the most criticised element of the S8 and S8+ so it wouldn't be too surprising to see Samsung focus on changing its position, perhaps beneath the display?

PocketNow recently reported this would be the case based on some unnamed industry sources cited by Korean media, though KGI reports this won't happen until the Note 9. Apparently the S9 will see the sensor moved to a more ergonomic position, but not under the screen.

Another rumour suggests the S9 will take on a modular design, similar to the Motorola Moto Z series. Eldar Murtazin doesn't reveal his source but claims the S9 will be able to accommodate one mod at a time, though several mods could be stacked on top of each other. It's still early days though so keep the salt handy for now.

  • Screen sizes reported to remain same as S8 and S8+
  • Infinity display expected again
  • Super AMOLED panel and Mobile HDR Premium both likely

The Samsung Galaxy S9 and the S9+, will no doubt continue the trend of the large display, minimal footprint. The S8 has a 5.8-inch screen, while the S8+ has a 6.2-inch screen, though thanks to their 18.5:9 ratios, their bodies are narrower than other handsets with smaller displays.

Whether the S9 will increase its display size further remains to be seen for now, though Korean site The Bell claims the Infinity Display will remain a key focus for the 2018 flagship. According to a PocketNow report, Korean Media has claimed the S9 and S9+ will both retain the current screen sizes so 5.8-inch and 6.2-inch respectively.

We'd expect the panel to stick with Super AMOLED, given it has offered Samsung so much success in the last few years and we'd also expect to see Mobile HDR on board again. By 2018, this latter feature is likely to be more prominent too as more content becomes available to take advantage of it.

Will Samsung increase the resolution from Quad HD+? Who knows. It wouldn't be too shocking to see a 4K display, especially since Sony offers one on its Xperia XZ Premium and given the trend for VR, but for now, it's guesswork.

  • Great performer expected
  • Possibility of dual-rear camera setup
  • Super slow-motion reported

The Samsung Galaxy S devices have offered excellent camera functionality since the Galaxy S6, improving year-on-year, so we'd expect the same from the Galaxy S9.

There aren't any rumours surrounding megapixels as yet, but expect a great performer, wide aperture and more advanced features, as is normally the way with a new flagship. Iris scanning is present on the Galaxy S8 and S8+ and it works brilliantly so we'd expect to see the technology appear on the S9, probably further improved again. There has been a Tweet to suggest the S9 will feature a 3D sensor front camera, though no further information was revealed.

The Galaxy Note 8 features a dual-rear camera, following the trend set by LG, Huawei and Apple. It was the first Samsung device to offer this but it wouldn't be too surprising to see the S9 follow suit as it normally brings in a few of the standout features from the Note series.

There have also been rumours to suggest Samsung is working on a 1000fps image sensor, which will allow the S9 to be capable of super slow-motion video recording, like the Sony XZ Premium, which offers 960fps. Samsung is apparently working on building the sensor itself rather than outsourcing to a third-party.

In other sensor news, Samsung has also announced two new ISOCELL sensors in the form of the Fast 2L9 and Slim 2X7, both of which are claimed to offer detailed pictures in low-light environments without a camera bump. There is currently no word as to whether either will be associated with the S9 or S9+ however.

  • Latest processor from Exynos or Qualcomm likely
  • Increase in RAM plausible

Given the Galaxy S9 and S9+ will be flagship devices, powerful hardware is pretty much a given. We can therefore expect the latest processor from Exynos or Qualcomm under the hood, though which one will probably be region specific as it has been the last couple of years.

Supporting this idea, it's been claimed we will see the Qualcomm Snapdragon 845 chipset appear in the Galaxy S9, possibly as an exclusive for a while again, like the SD835 in the S8 and S8+, but we will no doubt see Exynos is some regions too. 

The S8 and S8+ both have 4GB of RAM and 64GB of internal storage, as well as microSD. Whether we will see any of these numbers increase isn't currently known but we wouldn't be surprised to see a jump in RAM to 6GB, especially given some devices like the OnePlus 5 and Note 8 already offer this.

Battery-wise, again it is not clear if we will see an increase in capacity for the S9, but there will no doubt be improvements in performance from the processor and the software, even if the capacity stays the same. USB Type-C is almost a certainty, while the 3.5mm headphone jack will probably remain questionable until launch, as it did with the S8 and S8+. 

  • Android O with TouchWiz expected
  • Bixby voice assistant likely 

The Samsung Galaxy S9 and S9+ will no doubt launch on Android Oreo. It will also have Samsung's TouchWiz software over the top, which has been hugely refined over the last couple of years and will therefore probably offer even further improvements. 

It's too early to tell what kind of features will be on board as yet, but they will likely incorporate what we're expecting from Android Oreo, while also offering some Samsung-specific features too. We're expecting Bixby to be on board like the S8 and S8+, probably with some advancements, as well as Google Assistant.

For now, the Samsung Galaxy S9 and S9+ are pretty much all guesswork. They will no doubt bring a host of improvements over the Galaxy S8 and S8+, as all succeeding flagships do but nothing has been confirmed as yet.

We'll keep this feature updated with any rumours that appear regarding the Galaxy S9 and S9+. If you're getting itchy feet and the S8 and S8+ don't tickle your fancy, it's worth having a look at our Note 8 feature for now to see if that device might be able to tick your boxes.