ScrollView vs FlatList vs FlashList: Choosing the Right React Native List Component

React Native apps commonly suffer performance issues not due to the framework itself, but because developers use the wrong list component or misconfigure the right one. ScrollView renders all children at once and suits only small, fixed content, while FlatList and SectionList offer virtualization for hundreds to low thousands of items. Shopify's FlashList provides aggressive view recycling and is recommended for large feeds, catalogs, and chat interfaces handling thousands of items. Key performance problems fall into three categories: mount cost, scroll frame cost, and memory cost, each requiring a different optimization strategy. Common mistakes include mapping API results directly into a ScrollView and nesting vertical FlatLists inside vertical ScrollViews, both of which break windowing and cause jank.