App icons need multiple sizes for different contexts. iOS requires sizes from 29x29 to 1024x1024 (App Store). Android uses 48x48 (mdpi) to 512x512 (Google Play). Creating all variants from a single high-resolution source ensures consistency.
The recommended approach is to design at 1024x1024 and resize down to each required dimension. This ensures the icon looks good at all sizes. Avoid fine details that become invisible at smaller sizes.
With ImgTools, upload your 1024x1024 icon design and resize to each needed dimension. Common iOS sizes are 29x29, 40x40, 60x60, 76x76, 83.5x83.5, and 1024x1024. Common Android sizes are 48x48, 72x72, 96x96, 144x144, 192x192, and 512x512.
Save each size as PNG with transparency. App stores require PNG format for icon submissions.
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