Color setting works in Simulator but not in app

This code snippet works in app simulator but seems to have no effect on the color when automating from app:

input(name: "backColor", type: "string", title: "Set the color of ${fancyDeviceString(colorDimmers)}", description: null, required: false, defaultValue: "#00acff")
dimmer.setColor([hue: backColor, saturation: 100, level: nextLevel])

Quite puzzling. What am I doing wrong here?

(This is from my edit of the Gentle Wake Up app to add background color to this timer which I use for everything other than waking up :wink:)

What value are you inputting for “backColor”?

setColor takes a Hue in the form of a color wheel degrees number (mapped 0 to 100, I think, rather than 0 to 360), not a string.

But please check: first (Read The Fancy Manual, please).