Performance & Accessibility

Delivering a great mobile experience requires attention to device performance and accessibility standards.

Performance Optimization

1. View Calculation Efficiency

• Keep your widget construction functions lightweight. Do not compute expensive statistical aggregations or parse large JSON payloads inside your UI tree builders.
• Cache pre-computed results in your Store and update them on worker threads.

2. Choose the Right List Container

• Small collections (< 30 items): Use Column inside a ScrollView.
• Large or dynamic datasets (> 30 items): Always use the virtualized List widget to recycle view allocations and keep memory consumption constant.

3. Image Sizing & Memory

• Mobile devices have strict per-process RAM limits. Avoid bundling high-resolution 4000x3000 photos for an avatar that renders at 96x96 pixels.
• Downscale image assets to their display resolution before placing them in the project.

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Accessibility Best Practices

1. Touch Target Sizes

• Ensure interactive elements have comfortable touch targets (minimum 48x48 dp) so users can tap them easily without precision strain.

2. Meaningful Color Contrast

• Test foreground text contrast against your background colors.
• Never communicate state exclusively through color (e.g. green/red indicators). Always combine colors with descriptive icons or text labels.

3. Screen Reader Labels (TalkBack)

• Supply meaningful alt descriptions on all Image widgets that convey content.
• When creating icon-only buttons, pair the icon with descriptive accessibility text or labels.