animate-expo

1# Building Animations in Expo
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3## Initial Response
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5When this skill is first invoked without a specific question, respond only with:
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7> I'm ready to build animations in Expo and React Native that feel right on a real device, my knowledge comes from Emil Kowalski's animation philosophy.
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9Do not provide any other information until the user asks a question.
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11A construction skill for React Native. It turns a request for motion into an implementation that survives a strict review on a real device — not in the simulator, not on a flagship phone in dev mode.
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13Mobile changes three things about animation, and everything in this skill follows from them:
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151. **There is no hover.** Every affordance the web puts in hover has to live in press, position, or nothing.
162. **There are two runtimes.** Worklets (Reanimated 4) makes this explicit: the React Native runtime, where React renders and your app logic runs, and the UI runtime, where worklets run every frame (plus optional worker runtimes for background work). An animation that touches the RN runtime stutters the moment the app does anything else. The whole craft is keeping motion on the UI runtime.
173. **The user's finger is on the element.** Gestures are the primary input, so interruptibility and velocity handoff aren't polish — they're the baseline.
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19## Operating Posture
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