Display sizing

A Home Assistant dashboard designed in a desktop browser often renders at the wrong size on an Android wall panel: cards too large with clipped edges, or too small. A phone usually stays broadly in step with the desktop, but panels frequently do not, because their makers ship a system density and font scale that are poorly matched to the physical display. The panel app gives you two controls, Logical density (dpi) and Text size, in Install, then Display sizing, to bring the layout and the text back in line. You usually need both.

Experimental

The controls work, but the right values for each panel are not settled. Treat density and text size as something to experiment with rather than a finished feature. Feedback on values that work well for a given panel is welcome.

Using it

The Display sizing card on the panel’s Install tab sets a custom logical density and text size, applies them live, or resets to Android’s factory base density. Both survive a reboot, because they are Android system settings.

Note

This needs an approved privileged route: normally the vendor’s su or the root helper. A compatible unrooted panel whose optional enhanced access has already been approved on the panel can also make these exact display changes. Where no supported route is ready, the card stays visible but locked.

To tune it, open the same dashboard in a desktop browser for reference. Lower the density until the layout matches (more cards fit), then nudge the text size until the text matches. Good values depend on the installation as well as the model: the panel’s resolution, how far away people stand and how the dashboard is designed.

Some supported models ship a recommended density, and most of those a text size too. When Panel Assistant sets up such a panel without a privileged route, it applies them once over its ADB connection, and removing the app through Panel Assistant puts the previous values back.

The two controls

Control	What it changes	Mechanism
Logical density (dpi)	The whole layout. The effective viewport in dp is physical px ÷ (density / 160). A lower density fits more, closer to a desktop’s wider viewport; a higher one is larger.	wm density <n>
Text size	Text in the dashboard. Android’s system font scale becomes the WebView’s textZoom (textZoom = scale × 100).	settings put system font_scale <f>

Android’s wm density output calls the factory base value Physical density. That label is misleading: it is the density Android uses for layout once an override is reset, not a measurement of the display’s pixels per inch. The panel app reports it as the factory base, and shows a physical PPI only for hardware profiles whose screen dimensions have been checked independently.

Changing density alone scales the layout but can leave text the wrong size compared with the desktop; the font scale corrects the text. Tuning the two together is what brings a panel in line with the browser the dashboard was designed in.