Both run Android 7.0 Nougat, with the latest edition of Samsung's TouchWiz UI on top of it. This is the most minimal, most user-friendly version of Touchwiz we've ever used, but it can still be a little confusing to first-time Samsung owners and long-time Galaxy fans alike.
TouchWiz is overflowing with features, hidden options and multiple ways of getting things done, so knowing how to dig down and uncover the juicy bits is crucial for getting the best out of your new handset. We'll show you how to do 'em all, right here.
1) Rearrange the on-screen buttons
So the Galaxy S8's eye-catching curves convinced you to make the switch to Samsung after years of using another brand. It can be a little tricky to adjust, especially because Samsung insists on putting the on-screen Back and Recents keys the wrong way round (if you've used any other Android phone, that is).
Thankfully, you can now flip them back to the way you remember. Just head to the Settings app, tap Display, and then tap Navigation Bar. Tap Button layout and you can reverse the layout to something a little more familiar.
You can adjust the sensitivity of the digital home button here, too - or change the navigation bar's background colour to suit whatever wallpaper you're using.
2) Pick your app drawer preference
Android owners will feel right at home with Samsung's app drawer, which neatly hides and organises all your installed apps and keeps your homescreens free for widgets.
How you open it is up to you, though: either with a familiar drawer icon in the bottom row of homescreen icons, or with a simple swipe up or down anywhere onscreen. Both options are in Display -> Home Screen. Tap on Apps Button and choose the one that best suits you.
Apple owners might not want an app drawer at all, and that's fine: head to Display -> Home Screen and tap Home Screen Layout. Now you can ditch the drawer altogether for multiple home screens filled with apps, in the order you choose.
3) Search for anything on your phone
By the time you've filled your phone with apps and games, it can be tricky to remember where you left all your icons - especially if you chuck them into folders and rarely use them.
The search bar built into the app drawer can help you out, though. Just swipe down anywhere onscreen, or tap the app drawer icon if you've got it enabled, then tap on "Search phone" at the top of the screen. This'll search through any installed apps, as well as calendar appointments, SMS messages, and Settings pages, which should help you get to where you want to be that little bit quicker than doing everything manually.
4) Secure your phone with fingerprints, iris scanning or facial recognition
You've got plenty of choice when it comes to keeping the Galaxy S8 safe: fingerprint scanning, facial recognition, and iris scanning, on top of the usual onscreen passwords, PINs and patterns. You could just opt for one of these, but we've found that a combination is much more convenient.
Add a password by going to Settings -> Lockscreen and Security, and registering your face, fingerprint and iris. Each one has its own sub-menu on this screen. You'll also need to set a PIN, password or pattern before you can use biometrics, and you can only use one of either facial or iris scanning at once.
With a registered fingerprint, onscreen password and either iris or facial scanning enabled, you'll have three ways to quickly unlock your phone.
5) Sleep better by turning on the Blue light filter
We all like to use our phones in bed, catching up on the day's news, or simply scrolling through Facebook, but it could be impacting your sleep. The blue light pumped out by the screen can trick your brain into feeling more alert and awake, when you should be resting.
Samsung's got an easy fix, though, in the form of a 'Blue Light filter'. You can turn this on manually, either by going to Display -> Blue Light Filter in the Settings app, or by pulling down the notification tray and turning it on there instead. This strips out the blue light, leaving your screen looking warmer and yellower, but without confuddling your brain while you're glued to the phone at night.
Even better, you can set it to a schedule; either set one up manually, or leave it on automatically between sunset and sunrise. Both options are in the Blue Light Filter screen in the Display page of the Settings screen.
6) Set up edge panels
These handy shortcuts pop out from the edge of the curved screen - hence the name. There are plenty to choose from, including app shortcuts, phonebook contacts, the always-handy Smart Select panel, a Clipboard showing all the text and images you've copied recently, weather, quick tools, a calendar, sports, finance, news and other reminders. Basically, there's masses of them.
Only a few are turned on by default, though, and the handle that you have to swipe to open up the edge panels might not be in the best place for your fingers. To change it, go to Settings -> Display -> Edge Screen and tap on Edge Panels.
From here, you can toggle on different panels, or tap the three dots in the top right and select Handle Settings to move the location of the trigger, make it bigger, or turn it transparent so it doesn't get in the way of your apps.