diff --git a/native/navigation/nav-from-redux-handler.react.js b/native/navigation/nav-from-redux-handler.react.js
--- a/native/navigation/nav-from-redux-handler.react.js
+++ b/native/navigation/nav-from-redux-handler.react.js
@@ -4,13 +4,16 @@
 
 import { setNavStateActionType } from './action-types.js';
 import { NavContext } from './navigation-context.js';
+import type { MonitorActionState } from '../redux/dev-tools.react.js';
 import { useSelector } from '../redux/redux-utils.js';
 
 const NavFromReduxHandler: React.ComponentType<{}> = React.memo<{}>(
   function NavFromReduxHandler() {
     const navContext = React.useContext(NavContext);
 
-    const navStateInRedux = useSelector(state => state.navState);
+    const navStateInRedux = useSelector(
+      (state: MonitorActionState) => state.navState,
+    );
 
     const dispatch = React.useMemo(() => {
       if (!navContext) {
diff --git a/native/redux/dev-tools.react.js b/native/redux/dev-tools.react.js
--- a/native/redux/dev-tools.react.js
+++ b/native/redux/dev-tools.react.js
@@ -1,5 +1,6 @@
 // @flow
 
+import type { NavigationState } from '@react-navigation/core';
 import * as React from 'react';
 
 import { actionLogger } from 'lib/utils/action-logger.js';
@@ -7,9 +8,18 @@
 
 import { setReduxStateActionType } from './action-types.js';
 import { useSelector } from './redux-utils.js';
+import type { AppState } from './state-types.js';
 import { setNavStateActionType } from '../navigation/action-types.js';
 import { NavContext } from '../navigation/navigation-context.js';
 
+type MonitorAction =
+  | { +type: 'DISPATCH', +state: string, ... }
+  | { +type: 'IMPORT', ... };
+export type MonitorActionState = $ReadOnly<{
+  ...AppState,
+  +navState: NavigationState,
+}>;
+
 const DevTools: React.ComponentType<{}> = React.memo<{}>(function DevTools() {
   const devToolsRef = React.useRef();
   if (
@@ -79,7 +89,7 @@
   );
 
   const setInternalState = React.useCallback(
-    state => {
+    (state: MonitorActionState) => {
       const { navState, ...reduxState } = state;
       if (navDispatch) {
         navDispatch({
@@ -104,7 +114,7 @@
   );
 
   const handleActionFromMonitor = React.useCallback(
-    monitorAction => {
+    (monitorAction: MonitorAction) => {
       if (!devTools) {
         return;
       }