How Samsung DeX works


Samsung DeX is an extension of Android N's Multi-Window mode. Additional code development has been added by Samsung to create a more robust experience and to integrate it with Samsung value-added features, such as the Iris scanner.

There are no new Samsung APIs that need to be used to launch apps in Samsung DeX. However, apps must stringently adhere to a number of Android N Multi-Window standards to open in Desktop Mode. Desktop Mode includes all of the advanced, multitasking features built in to the Samsung DeX UI.

Samsung DeX device requirements

To run Samsung DeX the following hardware and software requirements must be met.

  • Mobile Device: Samsung Galaxy S8, S8+.

  • External Display: FHD (16:9 ratio) supported, HDMI display (Monitor, TV, Projector).

  • Peripherals: DeX Station, Samsung branded fast charger, mouse and keyboard (BT, USB or RF type).

  • OS: Android N (SDK 24 or above).

Phone Mode Samsung DeX
Resolution WQHD FHD
DPI 640dpi (xxhdpi) 160 dpi (mdpi)
Orientation Portrait Landscape
Screen size - xLarge
Peripherals N/A 1. Display connection required
2. Mouse required and keyboard recommended

As shown in the screenshot below, a number of system configuration changes occur when a device switches from mobile to Samsung DeX mode. For more details on how to set up the configuration changes, see the section: Modifying Apps for Samsung DeX.

Figure 1: Samsung mobile VS. Samsung DeX Desktop Mode

Setting up Samsung DeX

To switch into Samsung DeX, follow these steps:

  1. 1.

    Connect the DeX Station to an external monitor using a HDMI cable.

  2. 2.

    Connect the DeX Station to a power source using a Samsung branded fast charger (fast chargers have a lighting bolt symbol on them).

  3. 3.

    Connect the keyboard and mouse to the mobile device through Bluetooth. Alternatively, connect the mouse and keyboard via USB.

  4. 4.

    Place the mobile device on the DeX Station.

Figure 2: Mobile mode VS Desktop mode Figure 2: Samsung DeX station

Setting DeX features

Samsung DeX's introduces a number of new features to the Android experience. Some of these features include:

Category Feature
Basic app interaction Interactive scroll bar
Contextual menu
Keyboard shortcuts
Mouse pointer
Horizontal navigation
Zoom in / out
Enhanced interaction Drag & drop
Click & drag (selection)
Text selection (double-click)
New window
Mouse-over focus
Desktop Mode enhancements Mouse and keyboard support
Re-sizable Multi-Window
Control bar buttons
Window active / inactive
Switch windows (Alt + Tab)
Enhanced notifications
Figure 3: Samsung DeX features Figure 3: Samsung DeX features

About Samsung DeX app optimization

Samsung DeX window types

When an app is launched in Samsung DeX, it adopts 1 of 3 different windows types:

  1. 1.

    Resizable Window: Apps that comply with Android N Multi-Window standards. They operate in Free-Form Multi-Window Mode and can be re-sized according to need.

  2. 2.

    Fixed-size Window: Apps that do not comply with Android N Multi-Window standards. They only operate in a fixed mobile dimension and cannot be re-sized.

  3. 3.

    Not supported:Apps that are widget based only, or impractical to use in Samsung DeX. For example, Samsung Car mode. These apps do not work in Samsung DeX. Apps that also require finger-touch and restrict the use of a mouse do not work.

Figure 5: Differences in display modes Figure 5: Differences in display modes

Samsung DeX target SDK version

OS Version Multi-Window Support
SDK 24 and above Yes (Resizable Activity = TRUE)
Not declared (Resizable Activity not declared) : No re-sizable Window
No: No re-sizable Window
SDK 23 and below Yes: No re-sizable Window
No: No re-sizable Window