Windows 10 using Continuum support in VDA 7.14, VDA 7.15, and all Citrix Receiver platforms
In version 7.14 & 7.15 of XenApp and XenDesktop VDA and Windows Receiver, any touch-enabled device that connects/roams/reconnects to a Windows 10 VDA starts in tablet mode by default. This is the behavior whether or not the touch-enabled device was connect to a keyboard/mouse.
 
Enhanced support for Windows 10 using Continuum in VDA 7.16 (and higher) and Receiver for Windows 4.10
From XenApp and XenDesktop VDA 7.16, this feature has been enhanced, and support for Windows 10 Continuum has been expanded. In this release, users can:

• Start a session in desktop mode when either a keyboard or a mouse or both are attached.
• Choose to start their session in tablet mode or desktop mode.
• Toggle the mode mid-session if the user adds or removes mouse/keyboard on the touch-enabled device.

We detect the presence of keyboard/mouse on a touch-enabled client and put the client in desktop mode if either of the devices are present. A touch-enabled client is put in tablet/mobile mode if none of those devices are present. This happens both upon connect/reconnect as well as dynamic attachment/detachment of a keyboard/mouse.
 
Windows 10 Continuum support Configuration
XenServer 7.2
XenServer 7.2 integrates with the XenDesktop VDA, changing the hypervisor to enable the virtual firmware settings for 2-in-1 devices. Windows 10 loads the GPIO driver on the target virtual machine based on this updated BIOS. It is used for toggling between tablet and desktop modes within the virtual machine.
 
For each Windows 10 VM on which you want the feature enabled, run the XenServer CLI command to allow laptop/tablet switching:
xe vm-param-set uuid=<VM_UUID> platform:acpi_laptop_slate=1
 
Important: Updating the base image for an existing machine catalog after changing the laptop/tablet switching setting doesn't affect any previously provisioned VMs. After making a change in the XenServer Windows 10 VM base image, create a catalog, choose the updated base image, and provision a new Machine Creation Services (MCS) machine.
 
Windows 10 VDA 7.16
On the Windows VDA machine, navigate to Settings => System => Tablet Mode.
Choose the settings as shown:

Note that the above settings are enabled by default on Windows 10 7.16 VDAs
To disable or enable the feature on Windows 10 7.14/7.15 VDAs, configure this registry setting:
HKEY_LOCAL_MACHINE\Software\Citrix\Sessions
Name: CitrixEnhancedUserExperience
Type: REG_DWORD
Value:
0 (Disable)
1 (Enable)
 
Feature Minimum Requirements

• XenApp and XenDesktop VDA 7.16 (Windows 10)
• Receiver for Windows 4.10
• XenServer 7.2

Feature Limitations
Web Receivers do not support the Windows 10 Continuum automatic tablet/desktop mode switching feature. 
 

Windows 10 using Continuum is a Microsoft Windows feature that allows touch-enabled devices such as Windows phones to connect to a monitor, keyboard and mouse.