How does Flutter achieve consistent 60fps rendering?
Why Interviewers Ask This
Advanced questions like this reveal whether a candidate has internalized Flutter deeply enough to make architectural decisions. Strong answers demonstrate both breadth and depth of experience.
Answer
Flutter achieves consistent frame rates by owning every pixel on the screen through its own graphics engine (Skia, now transitioning to Impeller). Unlike React Native which bridges to native components, Flutter renders its own widgets directly to the canvas — there is no OEM widget translation layer that could cause jank. The Dart VM's low-latency garbage collector avoids long GC pauses. Flutter's animation system is synchronized with the display refresh rate (vsync). And const widgets, RepaintBoundary, and lazy list builders prevent unnecessary work each frame.
Common Mistake
Many candidates answer correctly but can't explain the 'why'. Always be prepared to justify your answer with a concrete example or use case from your Flutter experience.