RN

Test yourself

Quiz — Multiple Choice

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Score 0 / 0 answered · 65 total
  1. Q1What does Time-to-Interactive (TTI) measure?Optimization
  2. Q2Why does Hermes improve startup time?Optimization
  3. Q3A component wrapped in React.memo still re-renders every time. Most likely cause?Optimization
  4. Q4Best key for a list of items that can reorder, insert, or delete?Optimization
  5. Q5How do you keep an animation smooth while the JS thread is busy?Optimization
  6. Q6Most common source of a memory leak in a React Native screen?Optimization
  7. Q7What's the right first step before optimizing performance?Optimization
  8. Q8Which approach actually shrinks a large JS bundle?Optimization
  9. Q9A modern recycling list (FlashList v2) requires what?Optimization
  10. Q10Which removes the legacy bridge serialization bottleneck?Optimization
  11. Q11Heavy work must run after a screen transition without dropping frames. Best tool?Optimization
  12. Q12Where do you confirm WHY a component re-rendered?Optimization
  13. Q13What does 'on-device inference' mean?On-Device AI
  14. Q14Which RN architecture does the on-device AI runtime require?On-Device AI
  15. Q15Why can't you use Expo Go with it?On-Device AI
  16. Q16What must you call before any model API?On-Device AI
  17. Q17Approximate footprint of a 1B-parameter on-device LLM?On-Device AI
  18. Q18You must leave an LLM screen mid-generation. Correct handling?On-Device AI
  19. Q19Why prefer a quantized model (SpinQuant / 8da4w)?On-Device AI
  20. Q20Best way to load a multi-hundred-MB model?On-Device AI
  21. Q21Default hardware backend for most models on both platforms?On-Device AI
  22. Q22The library is pre-1.0. What's the senior practice?On-Device AI
  23. Q23Why does the LLM batch token emissions (~10 tokens / 80ms)?On-Device AI
  24. Q24How do you bound an LLM's context memory?On-Device AI
  25. Q25Why does FlashList outperform ScrollView for a 10k-row list?Performance
  26. Q26Which pair of properties is GPU-cheap to animate?Performance
  27. Q27What does the React Compiler do?Performance
  28. Q28A synchronous Turbo Module method should stay under ~16ms because…Performance
  29. Q29@expo/ui's universal components render as…Native UI
  30. Q30Why can `{items.length && <List/>}` crash in React Native?Native UI
  31. Q31What does React Query's staleTime do?Data
  32. Q32Where should auth tokens be stored in an Expo app?Data
  33. Q33Three independent API calls should be run with…Data
  34. Q34A heavy native (Turbo Module) computation should run…Performance
  35. Q35Why might you remove the @formatjs Intl polyfills?Performance
  36. Q36When a React Context value changes, which consumers re-render?Performance
  37. Q37How do you stop a native child view from being flattened away?Performance
  38. Q38You need a local native module. Can you run in Expo Go?Expo
  39. Q39Best way to handle safe areas in a scrollable screen?Expo
  40. Q40For responsive layout that survives rotation, use…Expo
  41. Q41Modern shadows in React Native use…Expo
  42. Q42The JS profiler shows nothing but the app is slow. Best next step?Native
  43. Q43How do you avoid a retain cycle with a Swift delegate?Native
  44. Q44How does Android deliver the right asset density efficiently?Native
  45. Q45Where should auth tokens live in a mobile app?Security
  46. Q46Certificate pinning prevents MITM — what's its main operational risk?Security
  47. Q47Which verifies that a genuine, untampered app is running?Security
  48. Q48react-native-executorch runs models in which format, on which runtime?On-Device AI
  49. Q49The main benefit of on-device LLM inference is…On-Device AI
  50. Q50An EAS Update (OTA) can ship…Releases
  51. Q51What gates whether an OTA update is compatible with an installed build?Releases
  52. Q52How do you assess whether a rollout is healthy?Releases
  53. Q53In the Expo Modules API, an AsyncFunction…Native
  54. Q54Callstack's brownfield approach packages the RN app as…Architecture
  55. Q55The canonical React Native upgrade diff comes from…Architecture
  56. Q56Declarative enter/exit animations in Reanimated v4 use…Expo
  57. Q57Which is owned by EAS remotely with autoIncrement?Releases
  58. Q58Props vs state — which is right?React
  59. Q59Why use FlatList over a ScrollView for a long list?Performance
  60. Q60Should you store derived data in state and sync it with a useEffect?React
  61. Q61A value changes every frame but shouldn't re-render the UI. Use…React
  62. Q62How do you fix a React Server Component fetch waterfall?React
  63. Q63Time-to-Interactive (TTI) measures…Performance
  64. Q64The 'use dom' directive makes a component…Expo
  65. Q65In an offline-first design, the source of truth is…Architecture