Samsung's upcoming three new wearable devices and a smartphone has changed the track. Samsung used Tizen, the open-source OS based on Linux, instead of Android for all these upcoming devices. Samsung's latest Tizen phone shows not much difference to the past ones, but they worked on some parts of design-notification bar, homescreen widget and apps drawer.
Samsung not unveiled what's their strategy for Tizen, use as a single OS or multi-OS strategy with Android. Here is some images of Samsung smartphone having Tizen OS:
The Tizen Homescreen:
Multi-Window running on Tizen 
The back of the Tizen prototype device
Tizen Notification Panel
Tizen OS Overview:
- Tizen uses the same button configuration as many Android Samsung phones, with Menu, Home, and Back buttons. Samsung's OS runs really, really well—it seems just as snappy and customizable as Android.
- Tizen has an app drawer, home screen pages, a pull-down notification panel, and widgets just like Android.
- There are third parties offering Android app support on Tizen, but Samsung wasn't demoing that.
- So far, Tizen seems a pretty accurate Android clone, but it's shocking how far along it is.
