Prompt for your app icon in 3 variations

Act as an app icon designer and an expert in prompts for image generators.

From my app's details, write me the prompt in English to generate my app icon in 3 style variations, all coherent with my brand.

App or software name: [E.G. Wanda Builds]
What it does in one sentence: [E.G. quick recipes app using what's in your fridge]
Symbol or core idea that represents the app: [E.G. a fork and a lightning bolt together, a house with a checkmark]
My brand colors: [E.G. magenta and purple on a dark background]
Main platform: [iOS / Android / both / web app]

Give me:
1. A base prompt in English with the symbol, palette, level of detail and "app icon, centered composition, no text, no letters" so the icon works on its own, without relying on text.
2. The 3 style variations built from that same base prompt, each one complete and ready to copy: (a) flat fill, (b) soft gradient using the brand palette, (c) outline/line on a solid background.
3. The exact sizes I should export based on the platform I picked (e.g. 1024x1024 for the App Store, 512x512 for Play Store's adaptive icon with safe margin for the circular/rounded crop, 180x180 and 32x32 if I also use it on the web).
4. A short tip to test the icon at real phone size (like 60x60) before deciding, because what looks great big sometimes gets lost small.

Rules: the icon must read clearly even at the smallest size, no text or letters inside the image, and all 3 variations must keep the same symbol and the same palette so they read as the same brand. If a detail is missing, mark it as [detail to verify] instead of making it up.