common-mobile-animation

name	common-mobile-animation
description	Motion design principles for mobile apps. Covers timing curves, transitions, gestures, and performance-conscious animations. (triggers: **/*_page.dart, **/*_screen.dart, **/*.swift, **/*Activity.kt, **/*Screen.tsx, Animation, AnimationController, Animated, MotionLayout, transition, gesture)

Mobile Animation

Priority: P1 (OPERATIONAL)

Native-feeling motion design. Optimize for 60fps and platform conventions.

Timing Standards

• Short: 100-150ms (Toggles, cell press)
• Medium: 250-350ms (Nav, modals)
• Long: 400-600ms (Shared element, complex state)
• Limit: Never >600ms.

Guidelines

• Easing: Use Curves.fastOutSlowIn (Material) or easeInOut (iOS). Avoid linear.
• Performance: Animate transform (Scale/Translation) and opacity. Avoid width/height.
• Gestures: Implement onPan / interactivePopGesture for fluid UX.
• Optimization: Use FadeTransition / SlideTransition over AnimatedBuilder for simple cases.

Animation Patterns

Anti-Patterns

• No Linear Easing: Feels robotic.
• No Layout Trashing: Avoid animating properties that trigger layout (width, padding).
• No Memory Leaks: Always dispose() AnimationControllers.
• No Blocking UI: Run heavy calculations outside animation frames.

Related Topics

mobile-ux-core | mobile-performance | flutter/animations