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Every image and video in the manifest is validated. Submissions that fail validation are rejected. For best results, export marketing assets as high-quality WebP. Use PNG only where it is strictly necessary, for example sharp logos on flat backgrounds.

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Images

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Videos

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Icon safe zone

iconUrl safe zone diagram. The icon canvas is 1024×1024 px with a centered safe zone circle at 83% (850×850 px). Logos must stay inside the safe zone circle.
Keep your logo within the safe zone circle. Do not pre-apply a corner radius. The Startale App rounds the corners for you.

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Hero image safe zone

heroImageUrl safe zone diagram. The canvas is 1200×630 px (1.91:1) with a vertically centered safe zone of 1200×420 px.
Keep important content within the vertically centered safe area. The hero image is used for the app grid card.
featuredBannerImageUrl safe zone diagram. The canvas is 2400×1260 px (1.91:1) with a centered safe zone of 1600×560 px.
Place logos, characters, title text, and other focal content inside the centered 1600×560 safe zone. Background imagery can extend to the full canvas, but anything load-bearing should sit within the safe area.

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App viewport

If screenCompatibility.desktop is omitted or false, your Mini App renders inside a 424×695 px portrait frame on desktop. When desktop: true, the iframe expands to fill the available browser viewport. When landscapeOnly: true, the effective canvas is 695×424 px, content is rotated 90° clockwise, and you should design at that effective size.

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Aspect ratio enforcement

Aspect ratios above are enforced at validation with a 1% tolerance. A 1200×640 image, for example, fails the 1.91:1 hero ratio check.

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Hosting recommendations

  • Serve images over a CDN with HTTP/2 and proper Cache-Control headers.
  • WebP delivers smaller files than PNG or JPG at the same visual quality. Use it where possible.
  • Avoid serving images from third-party redirect chains. Only 3 redirects are followed before the URL is rejected.