Kotlin Flow3 min read
StateFlow vs SharedFlow: When to Use Which ⚡
Kotlin's Flow APIs are powerful, but many devs trip up on StateFlow vs SharedFlow. Both are hot flows, but they shine in different situations.
September 23, 2025•By Divya
🔹 StateFlow
Holds a single up-to-date value (like LiveData).
Always has an initial value.
Collectors immediately get the latest state.
Perfect for UI state that needs to be observed continuously.
val uiState = MutableStateFlow(Loading)
👉 Use when you want your UI to always reflect the current state.
🔹 SharedFlow
No initial value.
Can replay a set number of past emissions.
Great for one-off events (navigation, toasts, error messages).
val events = MutableSharedFlow<UiEvent>()
👉 Use when you want to broadcast events without holding onto state.
TL;DR ⚡
StateFlow = state holder 🧠
SharedFlow = event broadcaster 📢
Think of it this way:
StateFlow: "What's the app's current mood?"
SharedFlow: "What just happened that the UI should react to?"
Key Differences Summary
| Feature | StateFlow | SharedFlow |
|---|---|---|
| Initial Value | Always has one | No initial value |
| Use Case | State management | Event broadcasting |
| New Collectors | Get latest value immediately | Only get future emissions |