Explain how you would optimize a mobile app that feels slow in common user flows. Describe how you would identify bottlenecks, what code patterns you would inspect first, and how you would decide which fixes to ship first.
How you profile and reproduce the issueHow arrays, strings, and hash-table usage affect performanceHow you reduce repeated work in hot pathsHow you prioritize fixes by user impactSlow startupDropped frames while scrollingLaggy screen transitionsHigh memory usageRepeated expensive computations