You can use Horizon Client with external displays and you can change screen resolutions.
When you connect a client device to an external display or projector, Horizon Client supports certain maximum display resolutions. You can change the screen resolution that the client device uses to allow scrolling a larger screen resolution.
Enlarging the Screen Resolution for a Remote Desktop
By default, the display resolution is set so that the entire remote desktop fits inside the client device, and the remote desktop icons and task bar icons are a certain size. If you use a larger resolution, the remote desktop still fits inside the client device, but the remote desktop and taskbar icons become smaller.
You can pinch your fingers apart to zoom in and make the remote desktop larger than the device screen. You can then tap and drag to access the edges of the remote desktop.
Changing the Display Resolution Setting
To change the resolution from a remote desktop or published application, tap to expand the Horizon Client Tools radial menu icon, tap the Settings (gear) icon, and tap Resolution. You can also change the resolution from the Horizon Client Settings window. Tap Settings at the bottom of the Horizon Client window and tap Resolution.
Certain options, including 3/4 Scaling and No Scaling, are not available on iPhone 6 when the device is in zoomed mode. To display these options, you must exit zoomed mode.
Using High Resolution Mode
You can use the High Resolution Mode feature to obtain the best display quality in remote desktops and published applications.
To enable High Resolution Mode from the Horizon Client Settings window, tap Settings at the bottom of the Horizon Client window, tap Resolution, and tap to toggle the High Resolution Mode setting to on. To enable High Resolution Mode from a remote desktop or published application, tap to expand the Horizon Client Tools radial menu icon, tap the Settings (gear) icon, tap Resolution, and tap to toggle the High Resolution Mode setting to on.
The High Resolution Mode feature has the following requirements and limitations.
You cannot use the High Resolution Mode feature for existing sessions. You must log out and log in to a new session for the feature to take effect.
You must have an iPad Pro, or an iPad or iPad mini with Retina display, to use the High Resolution Mode feature.
The remote desktop or published application must support the High Resolution Mode feature.
High Resolution Mode is disabled by default.
Using External Monitors and Projectors
You can use the Resolution setting to set a larger resolution for external monitors and projectors.
To display the keyboard and an expanded onscreen touchpad on the device while displaying the remote desktop on the projector or attached monitor, enable the Presentation Mode setting. The expanded touchpad and keyboard appear when you plug the device into the external monitor. The device detects the maximum resolution provided by the external display.
You can mirror the entire device display on a projector or attached monitor, including the Unity Touch sidebar, by turning off the Presentation mode setting. If you are connected to a remote desktop and the Presentation Mode setting is enabled, you can click Done to switch to mirror mode.
You can use the Keep the screen alive during Presentation setting to keep the display from turning off after a period of inactivity while in presentation mode.
You can configure these settings from a remote desktop or published application by tapping to expand the Horizon Client Tools radial menu icon and tapping the Settings (gear) icon. You can also configure these settings by tapping the Settings (gear) icon at the bottom of the Horizon Client window.
Hiding Sensitive Information on External Displays
When you use Horizon Client with an external monitor or projector, sensitive information, such as passwords and passcodes, is hidden to protect user data security.