Hi @astraios,
are you having black bars on the side of your tablet screen? if yes,
your main screen resolution and spacedesk Viewer resolution need to have the same aspect ratio (e.g. 4:3). Example for 4:3 aspect ratio: Main display screen 1920×1440 and viewer display screen 800×600. they both have the same aspect ratio.
You can change the resolution of spacedesk Viewer in spacedesk Viewer app menu.
In case of Desktop extension:
You can go to spacedesk Android viewer settings then check if “Use native android device resolution” is checked if not, please check it -> connect your android viewer to the server -> go to windows settings -> select the display # of your device -> go to resolution and change it to the native resolution of your android device.
In case of mirror/duplication:
Please go to spacedesk Android Viewer -> Settings -> Resolutions -> Choose Custom Resolution, please choose the resolution that matches your device’s aspect ratio – the one with (*) mark.