Force tablet app to display in "canvas size" rather than "window size" to user

[rsparks]

When opening my tablet app, it sits off centre like so:

But selecting "canvas size" while in preview mode helps it display correctly (centred). How can I permanently force setting on?

[v-qiaqi-msft]

Hi@rsparks,

Based on the issue that you mentioned, do you want to make your tablet app centered of the current screen?

Could you please share a bit more about the scenario, do you open this app from your ipad or the browser?
If you want to force the tablet app to keep "canvas size", I am afraid that there is no way to achieve this directly.

As an alternative solution,  navigate to File → App settings → Screen size + orientation and then scroll down to Advanced Settings. Toggle the setting Scale to fit so it’s turned off if it hasn’t been so. That activated the ability to create responsive apps and access those required information. 

Go to the "File" and select the settings under Experimental Features and check if this is turned on - if so, turn it off.

Further, I think the following blog could help you configure your tablet app:

https://lennartwoermer.de/2019/07/how-to-build-responsive-powerapps/ 

https://powerapps.microsoft.com/en-us/blog/new-properties-for-responsive-canvas-apps/ 

Hope it could help.

Best Regards,

Qi