App Not Using Full Screen on Mobile

[IPC_ahaas]

Is there a way to control how scalable an app is? It seems to be hardcoded for phones made years ago with 16x9 resolutions. Any tall phone has black bars at the top and bottom.

[Pstork1 · Accepted solution]

If you use the automatic scaling then no, but you can build the app using responsive design techniques.  Doing that you can fill the entire screen no matter what the resolution is.  Read the following article to learn how.  Create responsive layouts in canvas apps - Power Apps | Microsoft Docs

[Jasondefaoite]

This is not correct. 

Back in 2019 PowerApps would display full screen on mobile. MS changed this due to the status bar at the top of android / iOS to prevent a running PowerApp hiding them.

The current solution is black bars top/bottom of the display. While unlocking the aspect ratio and scaling it's possible to minimise the height of these bars, it's currently not possible to eliminate them as you suggest. 

While I understand the rationale behind the decision, I wish we hade the option to colour those black bars to at least make the app appear full screen.  

[Pstork1]

The black bars at the top and bottom of the screen in a responsive app on mobile are controlled by the system and have always been there. On IOS that is where the cutout is, so no app controls that space on IOS. But if you don't build the app using responsive techniques then there will be a larger black bar either top and bottom or one each side because the app is designed to scale the screen until it hits one of the edges and then fill in the other dimension with a black bar. That is what is being discussed here, not the system bars.