Before discussing about Samsung new ONE UI let’s have a brief introduction Samsung's custom user interface over the years. Samsung started its Android smartphone journey with their custom user interface TouchWiz. TouchWiz was heavily criticized for having too much bloat and slow performance. Due to bad experience of TouchWiz, people started switching their phones from Samsung. After that in 2016 Samsung introduced their new Experience UI on the top of Android Nougat.
image source: samsung

But why suddenly Samsung launched a whole new UI? 

Well in the age of bezel less, phones are getting taller day by day. In 2017 phones used to come with 16:9 aspect ratio. But now a days phones are coming with 18:9 or even 19.5:9. So Samsung felt a need to optimize their UI for taller phones and better one hand navigation. As the phone screens are getting taller your thumb can’t reach all the four corners of the screen. So Samsung has divided the whole UI into two halves. Upper half is viewing area and in the lower half you can interact with the UI.

New Features of ONE UI:

1.  Dark Mode:

image source: samsung

One of the best feature of new ONE UI is dark mode or night mode, whatever you want to call it. You can activate the dark mode by simply clicking the option in the settings menu or you can schedule the dark mode whatever time you want it to get activated. Basically it’s a dark theme which works on system menu, settings, dialer, messages and many more as of now there is no support for third party apps. Those who don’t like glare of white screen at night and prefers yellowish tint or blue light filter on screen it is the best feature. I personally like Dark Mode very much mainly for two reasons. Dark mode uses the full advantage of Super AMOLED Screens for displaying true black color and it causes less strain to the eyes. Secondly Dark Mode saves battery significantly compare to normal mode.

2. Redesigned Apps:


In this new ONE UI the system apps got major revamp. The official website says “focus on the task at hand.  The system apps are designed accordingly. So each app two sections. Upper half has viewing area and in the lower half you can interact with the UI. So that you don’t have any difficulties to reach on the top of the screen. As a result the new UI is more consistent and cleaner.
The app icons are changed too. They got more colorful and vibrant though everyone may not like the new icon pack. In my opinion the icon pack is too childish and cartoonish. It’s may be their strategy to get more young users as they are pushing Fortnite really hard for the Galaxy Note 9. Camera, Settings, Message and Gallery Apps got major revamp in terms of design for one hand operations.
ONE UI aims "be visibly comfortable." Samsung is trying to combine the software and hardware by using some colour tweaks to provide uniform experience. As an example if you are using red phone then you will see red accent here and there on your UI too.

New Home Screen, Gesture Navigation & Bixby 2.0:

You will get a newly designed homepage, it’s become cleaner and trendier tough you won’t feel this is a completely new design. The essence and touch of previous UI’s home screen is still there. First Apple introduced gesture control in iPhone X & now Google also introduced gesture control with Android Pie. Now you can swipe up on home screen to go menu and swipe down to open all the notifications. You can also disable he app drawer and move all the apps in home screen. In ONE UI you can perform tasks by gesture controls just like IOS has implemented it. Although OEMs like Xiaomi, OnePlus, Honor, Oppo also offers gesture navigation but in my opinion Samsung has done the best job, it seems well optimized and responsive.
Samsung’s voice assistant Bixby also gets a new makeover. You can swipe left to the home screen to land on the Bixby feed. Not like older UI’s the transition is very smooth and responsive. Bixby interface is redesigned according to the ONE UI design statement and it matches perfectly. Even though the functionality more or less remains the same.
These are three main feature new ONE UI offers. Although there is many new thing in ONE UI to write about like 

1. Dockless Dex

2. Always on Display

3. Smarter Camera

4. Lift to awake  



Phones Getting ONE UI Update:

According to Samsung, they are going to update all their flagship smartphones in S series and Note line up. The confirmed devices are listed below:  
1.       Galaxy Note 9
2.       Galaxy S9
3.       Galaxy S9+
4.       Galaxy Note 8
5.       Galaxy S8
6.       Galaxy S8+
 Samsung's new ONE UI is a welcome change. Samsung is eyeing the future Smart Phone trends by their new UI. Overall I am very impressed by this UI. I am very much excited to see how they implement the UI in fold-able smartphone.