The Samsung Galaxy S8 and S8+ only hit shelves a couple of 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 launches, 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 or S9+ before March or April 2018. 

The South Korean company's next device is instead rumoured to be the Galaxy Note 8, which is thought to be coming at the end of August, beginning of September.

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

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'd expect that to change once the Note 8 launches though so keep your eyes peeled towards the end of September.

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 it's still early days 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+, assuming there is one, 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

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.

The Galaxy Note 8 is rumoured to be coming with a dual-rear camera, following the trend set by LG, Huawei and Apple. If this speculation turns out to be accurate, 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. We will have to wait a few more months to see if Samsung does hop on the dual-camera bandwagon though so sit tight for now.

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

Given the Galaxy S9 will be a flagship device, 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. 

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 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 will no doubt launch on Android O, the name of which we don't know as yet. 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 O, 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 is pretty much all guesswork. It will no doubt bring a host of improvements over the Galaxy S8 and S8+, as all succeeding flagships do, but there are several devices in the pipeline set to arrive before it, such as the Pixel 2 and the Galaxy Note 8.

We'll keep this feature updated with any rumours that appear regarding the Galaxy 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.