EDIT: The app is called Measure. If it isn’t included on your iOS device already, it is a free download from the App Store. iMore has a good tutorial, as usual. https://www.imore.com/how-use-measure-app-ios-12
I was at my favorite restaurant – Tommy’s Mexican in SF (best tequila bar in the world) – and was once again admiring the little booth side flower holders. Pulled out my iPhone and used the built in Measurements app to quickly get the dimensions:
An hour or so of stumbling through Fusion 360 (I don’t know what I’m doing-- would have been MUCH longer without @jbpa’s plugin Need testers: TabGen (Fusion 360 Plug-in) improvements) and I had a workable design!
This is a draft print on BB plywood. Not sure what wood I’ll use in the end. And I might redo the design to use thicker material (I didn’t parameterize on the first pass. Oops).