diff --git a/README.md b/README.md
index 586c4213..d53f2f74 100644
--- a/README.md
+++ b/README.md
@@ -721,7 +721,34 @@ setOnArrival(null);
 | `setOnReroutingRequestedByOffRoute`   | `void`                                                | Called when rerouting is triggered by off-route |
 | `setOnTrafficUpdated`                 | `void`                                                | Called when traffic data is updated             |
 | `setOnRemainingTimeOrDistanceChanged` | `void`                                                | Called when remaining time or distance changes  |
-| `setOnTurnByTurn`                     | `{ navInfo: NavInfo }`                                | Called with turn-by-turn navigation info        |
+| `setOnTurnByTurn`                     | `TurnByTurnEvent[]`                                   | Called with turn-by-turn navigation info        |
+
+Turn-by-turn events include navigation state, distance and time estimates, the current step, and
+remaining steps. Step distances are in meters and durations are in seconds. `instruction`,
+`exitNumber`, and `fullRoadName` can be absent; an arrival instruction can also be empty.
+`roundaboutTurnNumber` is `-1` when the step is not in a roundabout.
+
+```tsx
+import { useEffect } from 'react';
+import { Maneuver, useNavigation } from '@googlemaps/react-native-navigation-sdk';
+
+const { setOnTurnByTurn } = useNavigation();
+
+useEffect(() => {
+  setOnTurnByTurn(events => {
+    const step = events[0]?.currentStep;
+    if (!step) {
+      return;
+    }
+
+    if (step.maneuver === Maneuver.TURN_LEFT) {
+      console.log(step.instruction ?? 'Turn left');
+    }
+  });
+
+  return () => setOnTurnByTurn(null);
+}, [setOnTurnByTurn]);
+```
 
 ### MapViewAutoController (useNavigationAuto hook)
 
diff --git a/example/src/screens/integration_tests/integration_test.ts b/example/src/screens/integration_tests/integration_test.ts
index c8e953cf..202fde23 100644
--- a/example/src/screens/integration_tests/integration_test.ts
+++ b/example/src/screens/integration_tests/integration_test.ts
@@ -77,6 +77,46 @@ const NAVIGATOR_NOT_READY_ERROR_CODE = 'NO_NAVIGATOR_ERROR_CODE';
 const NO_DESTINATIONS_ERROR_CODE = 'NO_DESTINATIONS';
 export const NO_ERRORS_DETECTED_LABEL = 'No errors detected';
 
+const validateTurnByTurnPayload = (
+  events: TurnByTurnEvent[]
+): string | null => {
+  const event = events[0];
+  if (!event) {
+    return 'Turn-by-turn event payload was empty';
+  }
+  if (
+    typeof event.navState !== 'number' ||
+    typeof event.routeChanged !== 'boolean'
+  ) {
+    return 'Turn-by-turn event had invalid navigation state fields';
+  }
+  if (!Array.isArray(event.getRemainingSteps)) {
+    return 'Turn-by-turn event had invalid remaining steps';
+  }
+
+  const step = event.currentStep ?? event.getRemainingSteps[0];
+  if (!step) {
+    return 'Turn-by-turn event did not include a step';
+  }
+
+  const numericStepFields = [
+    step.distanceFromPrevStepMeters,
+    step.timeFromPrevStepSeconds,
+    step.drivingSide,
+    step.stepNumber,
+    step.maneuver,
+    step.roundaboutTurnNumber,
+  ];
+  if (!numericStepFields.every(field => typeof field === 'number')) {
+    return 'Turn-by-turn step had invalid numeric fields';
+  }
+  if (step.instruction != null && typeof step.instruction !== 'string') {
+    return 'Turn-by-turn step had an invalid instruction';
+  }
+
+  return null;
+};
+
 type NativeModuleError = {
   code?: string;
 };
@@ -1911,8 +1951,15 @@ export const testNavInfoEventsAfterCleanup = async (testTools: TestTools) => {
 
   let phase: 'first' | 'second' = 'first';
 
-  setOnTurnByTurn(async (_events: TurnByTurnEvent[]) => {
+  setOnTurnByTurn(async (events: TurnByTurnEvent[]) => {
     if (phase === 'first') {
+      const payloadError = validateTurnByTurnPayload(events);
+      if (payloadError) {
+        setOnTurnByTurn(null);
+        failTest(payloadError);
+        return;
+      }
+
       // Received navInfo in first session — now cleanup and re-init
       phase = 'second';
       setOnTurnByTurn(null);
diff --git a/ios/react-native-navigation-sdk/NavModule.mm b/ios/react-native-navigation-sdk/NavModule.mm
index d8018575..a84f9078 100644
--- a/ios/react-native-navigation-sdk/NavModule.mm
+++ b/ios/react-native-navigation-sdk/NavModule.mm
@@ -1028,6 +1028,8 @@ - (NSDictionary *)getStepInfo:(GMSNavigationStepInfo *)stepInfo {
   [obj setValue:[NSNumber numberWithInteger:stepInfo.drivingSide] forKey:@"drivingSide"];
   [obj setValue:[NSNumber numberWithInteger:stepInfo.stepNumber] forKey:@"stepNumber"];
   [obj setValue:[NSNumber numberWithInteger:stepInfo.maneuver] forKey:@"maneuver"];
+  [obj setValue:[NSNumber numberWithInteger:stepInfo.roundaboutTurnNumber]
+         forKey:@"roundaboutTurnNumber"];
   [obj setValue:stepInfo.exitNumber forKey:@"exitNumber"];
   [obj setValue:stepInfo.fullRoadName forKey:@"fullRoadName"];
   [obj setValue:stepInfo.fullInstructionText forKey:@"instruction"];
diff --git a/src/native/NativeNavModule.ts b/src/native/NativeNavModule.ts
index 65934b55..0f9da6a5 100644
--- a/src/native/NativeNavModule.ts
+++ b/src/native/NativeNavModule.ts
@@ -131,12 +131,18 @@ type TurnByTurnEventSpec = Readonly<{
   getRemainingSteps: ReadonlyArray<StepInfoSpec>;
 }>;
 
+// This mirrors the fields emitted by Android's StepInfo and iOS's
+// GMSNavigationStepInfo. Keep it aligned with the public TurnByTurnStep type.
 type StepInfoSpec = Readonly<{
-  instruction: string;
-  distanceMeters: Double;
-  durationSeconds: Double;
-  maneuver: string;
-  position: LatLngSpec;
+  instruction?: string | null;
+  distanceFromPrevStepMeters: Double;
+  timeFromPrevStepSeconds: Double;
+  drivingSide: Double;
+  stepNumber: Double;
+  maneuver: Double;
+  roundaboutTurnNumber: Double;
+  exitNumber?: string | null;
+  fullRoadName?: string | null;
 }>;
 
 enum RouteStatusSpec {
diff --git a/src/navigation/navigation/types.ts b/src/navigation/navigation/types.ts
index 55426509..142d685a 100644
--- a/src/navigation/navigation/types.ts
+++ b/src/navigation/navigation/types.ts
@@ -26,6 +26,9 @@ import type {
   TravelMode,
   Waypoint,
   TermsAndConditionsUIParams,
+  DrivingSide,
+  Maneuver,
+  NavState,
 } from '../types';
 import { NavigationSessionStatus } from '../types';
 
@@ -550,8 +553,48 @@ export enum TaskRemovedBehavior {
   QUIT_SERVICE,
 }
 
-/**
- * Defines the turn-by-turn event data.
- */
-// eslint-disable-next-line @typescript-eslint/no-empty-object-type
-export interface TurnByTurnEvent {}
+/** Information about one step in a turn-by-turn navigation route. */
+export interface TurnByTurnStep {
+  /** The step instruction. It can be absent or empty for arrival steps. */
+  instruction?: string | null;
+  /** Distance from the previous step, in meters. */
+  distanceFromPrevStepMeters: number;
+  /** Estimated duration of the step, in seconds. */
+  timeFromPrevStepSeconds: number;
+  /** The side of the road used for this step. */
+  drivingSide: DrivingSide;
+  /** The zero-based index of this step in the route. */
+  stepNumber: number;
+  /** The maneuver to perform for this step. */
+  maneuver: Maneuver;
+  /** The number of the exit after entering a roundabout, or -1 when not applicable. */
+  roundaboutTurnNumber: number;
+  /** The route exit number, when available. */
+  exitNumber?: string | null;
+  /** The full road name, when available. */
+  fullRoadName?: string | null;
+}
+
+/** Defines the turn-by-turn event data. */
+export interface TurnByTurnEvent {
+  /** The current navigation state. */
+  navState: NavState;
+  /** Whether the route changed since the previous event. */
+  routeChanged: boolean;
+  /** Distance to the current step, in meters. */
+  distanceToCurrentStepMeters?: number;
+  /** Distance to the final destination, in meters. */
+  distanceToFinalDestinationMeters?: number;
+  /** Estimated time to the current step, in seconds. */
+  timeToCurrentStepSeconds?: number;
+  /** Distance to the next destination, in meters. */
+  distanceToNextDestinationMeters?: number;
+  /** Estimated time to the next destination, in seconds. */
+  timeToNextDestinationSeconds?: number;
+  /** Estimated time to the final destination, in seconds. */
+  timeToFinalDestinationSeconds?: number;
+  /** The step currently being navigated, when available. */
+  currentStep?: TurnByTurnStep;
+  /** The remaining route steps. This name mirrors the native event payload. */
+  getRemainingSteps: TurnByTurnStep[];
+}
diff --git a/src/navigation/types.ts b/src/navigation/types.ts
index ec857040..e80410ca 100644
--- a/src/navigation/types.ts
+++ b/src/navigation/types.ts
@@ -43,6 +43,76 @@ export enum NavState {
   STOPPED = 3,
 }
 
+/** The maneuver for a turn-by-turn navigation step. */
+export enum Maneuver {
+  UNKNOWN = 0,
+  DEPART = 1,
+  DESTINATION = 2,
+  DESTINATION_LEFT = 3,
+  DESTINATION_RIGHT = 4,
+  STRAIGHT = 5,
+  TURN_LEFT = 6,
+  TURN_RIGHT = 7,
+  TURN_KEEP_LEFT = 8,
+  TURN_KEEP_RIGHT = 9,
+  TURN_SLIGHT_LEFT = 10,
+  TURN_SLIGHT_RIGHT = 11,
+  TURN_SHARP_LEFT = 12,
+  TURN_SHARP_RIGHT = 13,
+  TURN_U_TURN_CLOCKWISE = 14,
+  TURN_U_TURN_COUNTERCLOCKWISE = 15,
+  MERGE_UNSPECIFIED = 16,
+  MERGE_LEFT = 17,
+  MERGE_RIGHT = 18,
+  FORK_LEFT = 19,
+  FORK_RIGHT = 20,
+  ON_RAMP_UNSPECIFIED = 21,
+  ON_RAMP_LEFT = 22,
+  ON_RAMP_RIGHT = 23,
+  ON_RAMP_KEEP_LEFT = 24,
+  ON_RAMP_KEEP_RIGHT = 25,
+  ON_RAMP_SLIGHT_LEFT = 26,
+  ON_RAMP_SLIGHT_RIGHT = 27,
+  ON_RAMP_SHARP_LEFT = 28,
+  ON_RAMP_SHARP_RIGHT = 29,
+  ON_RAMP_U_TURN_CLOCKWISE = 30,
+  ON_RAMP_U_TURN_COUNTERCLOCKWISE = 31,
+  OFF_RAMP_UNSPECIFIED = 32,
+  OFF_RAMP_LEFT = 33,
+  OFF_RAMP_RIGHT = 34,
+  OFF_RAMP_KEEP_LEFT = 35,
+  OFF_RAMP_KEEP_RIGHT = 36,
+  OFF_RAMP_SLIGHT_LEFT = 37,
+  OFF_RAMP_SLIGHT_RIGHT = 38,
+  OFF_RAMP_SHARP_LEFT = 39,
+  OFF_RAMP_SHARP_RIGHT = 40,
+  OFF_RAMP_U_TURN_CLOCKWISE = 41,
+  OFF_RAMP_U_TURN_COUNTERCLOCKWISE = 42,
+  ROUNDABOUT_CLOCKWISE = 43,
+  ROUNDABOUT_COUNTERCLOCKWISE = 44,
+  ROUNDABOUT_STRAIGHT_CLOCKWISE = 45,
+  ROUNDABOUT_STRAIGHT_COUNTERCLOCKWISE = 46,
+  ROUNDABOUT_LEFT_CLOCKWISE = 47,
+  ROUNDABOUT_LEFT_COUNTERCLOCKWISE = 48,
+  ROUNDABOUT_RIGHT_CLOCKWISE = 49,
+  ROUNDABOUT_RIGHT_COUNTERCLOCKWISE = 50,
+  ROUNDABOUT_SLIGHT_LEFT_CLOCKWISE = 51,
+  ROUNDABOUT_SLIGHT_LEFT_COUNTERCLOCKWISE = 52,
+  ROUNDABOUT_SLIGHT_RIGHT_CLOCKWISE = 53,
+  ROUNDABOUT_SLIGHT_RIGHT_COUNTERCLOCKWISE = 54,
+  ROUNDABOUT_SHARP_LEFT_CLOCKWISE = 55,
+  ROUNDABOUT_SHARP_LEFT_COUNTERCLOCKWISE = 56,
+  ROUNDABOUT_SHARP_RIGHT_CLOCKWISE = 57,
+  ROUNDABOUT_SHARP_RIGHT_COUNTERCLOCKWISE = 58,
+  ROUNDABOUT_U_TURN_CLOCKWISE = 59,
+  ROUNDABOUT_U_TURN_COUNTERCLOCKWISE = 60,
+  ROUNDABOUT_EXIT_CLOCKWISE = 61,
+  ROUNDABOUT_EXIT_COUNTERCLOCKWISE = 62,
+  FERRY_BOAT = 63,
+  FERRY_TRAIN = 64,
+  NAME_CHANGE = 65,
+}
+
 /**
  * Specify that the Navigation SDK should determine the appropriate day or night mode according to
  * user's location and local time.