diff --git a/packages/bottender/src/bot/Bot.ts b/packages/bottender/src/bot/Bot.ts
index 655ca6262..dae886e0e 100644
--- a/packages/bottender/src/bot/Bot.ts
+++ b/packages/bottender/src/bot/Bot.ts
@@ -183,56 +183,62 @@ export default class Bot<B extends Body, C extends Client, E extends Event> {
 
       const body = camelcaseKeysDeep(inputBody) as B;
 
-      const { platform } = this._connector;
-      const sessionKey = this._connector.getUniqueSessionKey(
-        body,
-        requestContext
-      );
-
-      // Create or retrieve session if possible
-      let sessionId: string | undefined;
-      let session: Session | undefined;
-      if (sessionKey) {
-        sessionId = `${platform}:${sessionKey}`;
-
-        session =
-          (await this._sessions.read(sessionId)) ||
-          (Object.create(null) as Session);
-
-        debugSessionRead(`Read session: ${sessionId}`);
-        debugSessionRead(JSON.stringify(session, null, 2));
-
-        Object.defineProperty(session, 'id', {
-          configurable: false,
-          enumerable: true,
-          writable: false,
-          value: session.id || sessionId,
-        });
+      const events = this._connector.mapRequestToEvents(body);
 
-        if (!session.platform) session.platform = platform;
+      const contexts = await pMap(
+        events,
+        async event => {
+          const { platform } = this._connector;
+          const sessionKey = this._connector.getUniqueSessionKey(
+            // TODO: may deprecating passing request body in v2
+            events.length === 1 ? body : event,
+            requestContext
+          );
+
+          // Create or retrieve session if possible
+          let sessionId: string | undefined;
+          let session: Session | undefined;
+          if (sessionKey) {
+            sessionId = `${platform}:${sessionKey}`;
+
+            session =
+              (await this._sessions.read(sessionId)) ||
+              (Object.create(null) as Session);
+
+            debugSessionRead(`Read session: ${sessionId}`);
+            debugSessionRead(JSON.stringify(session, null, 2));
+
+            Object.defineProperty(session, 'id', {
+              configurable: false,
+              enumerable: true,
+              writable: false,
+              value: session.id || sessionId,
+            });
 
-        Object.defineProperty(session, 'platform', {
-          configurable: false,
-          enumerable: true,
-          writable: false,
-          value: session.platform,
-        });
+            if (!session.platform) session.platform = platform;
 
-        await this._connector.updateSession(session, body);
-      }
+            Object.defineProperty(session, 'platform', {
+              configurable: false,
+              enumerable: true,
+              writable: false,
+              value: session.platform,
+            });
 
-      const events = this._connector.mapRequestToEvents(body);
+            await this._connector.updateSession(
+              session,
+              // TODO: may deprecating passing request body in v2
+              events.length === 1 ? body : event
+            );
+          }
 
-      const contexts = await pMap(
-        events,
-        event =>
-          this._connector.createContext({
+          return this._connector.createContext({
             event,
             session,
             initialState: this._initialState,
             requestContext,
             emitter: this._emitter,
-          }),
+          });
+        },
         {
           concurrency: 5,
         }
@@ -252,6 +258,8 @@ export default class Bot<B extends Body, C extends Client, E extends Event> {
       }
       const handler: Action<C, E> = this._handler;
       const errorHandler: Action<C, E> | null = this._errorHandler;
+
+      // TODO: only run concurrently for different session id
       const promises = Promise.all(
         contexts.map(context =>
           Promise.resolve()
@@ -277,17 +285,24 @@ export default class Bot<B extends Body, C extends Client, E extends Event> {
       if (this._sync) {
         try {
           await promises;
-          if (sessionId && session) {
-            session.lastActivity = Date.now();
-            contexts.forEach(context => {
+
+          await Promise.all(
+            contexts.map(async context => {
               context.isSessionWritten = true;
-            });
 
-            debugSessionWrite(`Write session: ${sessionId}`);
-            debugSessionWrite(JSON.stringify(session, null, 2));
+              const { session } = context;
 
-            await this._sessions.write(sessionId, session);
-          }
+              if (session) {
+                session.lastActivity = Date.now();
+
+                debugSessionWrite(`Write session: ${session.id}`);
+                debugSessionWrite(JSON.stringify(session, null, 2));
+
+                // eslint-disable-next-line no-await-in-loop
+                await this._sessions.write(session.id, session);
+              }
+            })
+          );
         } catch (err) {
           console.error(err);
         }
@@ -301,19 +316,27 @@ export default class Bot<B extends Body, C extends Client, E extends Event> {
         return response;
       }
       promises
-        .then((): Promise<any> | void => {
-          if (sessionId && session) {
-            session.lastActivity = Date.now();
-            contexts.forEach(context => {
-              context.isSessionWritten = true;
-            });
+        .then(
+          async (): Promise<any> => {
+            await Promise.all(
+              contexts.map(async context => {
+                context.isSessionWritten = true;
 
-            debugSessionWrite(`Write session: ${sessionId}`);
-            debugSessionWrite(JSON.stringify(session, null, 2));
+                const { session } = context;
 
-            return this._sessions.write(sessionId, session);
+                if (session) {
+                  session.lastActivity = Date.now();
+
+                  debugSessionWrite(`Write session: ${session.id}`);
+                  debugSessionWrite(JSON.stringify(session, null, 2));
+
+                  // eslint-disable-next-line no-await-in-loop
+                  await this._sessions.write(session.id, session);
+                }
+              })
+            );
           }
-        })
+        )
         .catch(console.error);
     };
   }
diff --git a/packages/bottender/src/bot/Connector.ts b/packages/bottender/src/bot/Connector.ts
index 82e3561f6..43623410f 100644
--- a/packages/bottender/src/bot/Connector.ts
+++ b/packages/bottender/src/bot/Connector.ts
@@ -1,16 +1,20 @@
 import EventEmitter from 'events';
 
 import Session from '../session/Session';
+import { Event } from '../context/Event';
 import { RequestContext } from '../types';
 
 export interface Connector<B, C> {
   client: C;
   platform: string;
-  getUniqueSessionKey(body: B, requestContext?: RequestContext): string | null;
-  updateSession(session: Session, body: B): Promise<void>;
-  mapRequestToEvents(body: B): any[];
+  getUniqueSessionKey(
+    bodyOrEvent: B | Event<any>,
+    requestContext?: RequestContext
+  ): string | null;
+  updateSession(session: Session, bodyOrEvent: B | Event<any>): Promise<void>;
+  mapRequestToEvents(body: B): Event<any>[];
   createContext(params: {
-    event: any;
+    event: Event<any>;
     session?: Session | null;
     initialState?: Record<string, any> | null;
     requestContext?: RequestContext;
diff --git a/packages/bottender/src/bot/__tests__/Bot.spec.ts b/packages/bottender/src/bot/__tests__/Bot.spec.ts
index 9da1a983e..460d4daaf 100644
--- a/packages/bottender/src/bot/__tests__/Bot.spec.ts
+++ b/packages/bottender/src/bot/__tests__/Bot.spec.ts
@@ -5,7 +5,6 @@ function setup({
   connector = {
     platform: 'any',
     getUniqueSessionKey: jest.fn(),
-    shouldSessionUpdate: jest.fn(),
     updateSession: jest.fn(),
     mapRequestToEvents: jest.fn(() => [{}]),
     createContext: jest.fn(() => ({})),
@@ -16,7 +15,7 @@ function setup({
     read: jest.fn(),
     write: jest.fn(),
   },
-  sync = false,
+  sync = true,
   mapPageToAccessToken,
 }) {
   const bot = new Bot({ connector, sessionStore, sync, mapPageToAccessToken });
@@ -85,7 +84,6 @@ describe('#createRequestHandler', () => {
     const { bot, connector, sessionStore } = setup({});
 
     connector.getUniqueSessionKey.mockReturnValue('__id__');
-    connector.shouldSessionUpdate.mockReturnValue(true);
     sessionStore.read.mockResolvedValue(null);
 
     const handler = () => {};
@@ -105,7 +103,6 @@ describe('#createRequestHandler', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => ({ event, session })),
@@ -129,10 +126,12 @@ describe('#createRequestHandler', () => {
 
     expect(receivedContext).toEqual({
       event: {},
+      isSessionWritten: true,
       session: expect.objectContaining({
         id: 'any:__id__',
         platform: 'any',
         user: {},
+        lastActivity: expect.any(Number),
       }),
     });
   });
@@ -152,7 +151,6 @@ describe('#createRequestHandler', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => context),
@@ -195,7 +193,6 @@ describe('#createRequestHandler', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => ({ event, session: undefined })),
@@ -223,7 +220,6 @@ describe('#createRequestHandler', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => ({ event, session: undefined })),
@@ -256,7 +252,6 @@ describe('#createRequestHandler', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => ({ event, session: 123456 })),
@@ -290,7 +285,6 @@ describe('#createRequestHandler', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => ({ event, session: 123456 })),
@@ -327,7 +321,6 @@ describe('#createRequestHandler', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => ({ event, session })),
@@ -353,6 +346,65 @@ describe('#createRequestHandler', () => {
     });
     Date.now = _now;
   });
+
+  it('should work with multiple events in one request', async () => {
+    const event1 = {};
+    const event2 = {};
+    const connector = {
+      platform: 'any',
+      getUniqueSessionKey: jest.fn(),
+      updateSession: jest.fn(),
+      mapRequestToEvents: jest.fn(() => [event1, event2]),
+      createContext: jest.fn(({ event, session }) => ({ event, session })),
+    };
+    const { bot, sessionStore } = setup({ connector });
+
+    connector.getUniqueSessionKey
+      .mockReturnValueOnce('1')
+      .mockReturnValueOnce('2');
+    sessionStore.read.mockResolvedValue(null);
+
+    const handler = () => {};
+    bot.onEvent(handler);
+
+    const requestHandler = bot.createRequestHandler();
+
+    const body = {};
+    await requestHandler(body);
+
+    expect(sessionStore.read).toBeCalledWith('any:1');
+    expect(sessionStore.read).toBeCalledWith('any:2');
+
+    expect(connector.getUniqueSessionKey).toBeCalledWith(event1, undefined);
+    expect(connector.getUniqueSessionKey).toBeCalledWith(event2, undefined);
+
+    expect(connector.createContext).toBeCalledWith(
+      expect.objectContaining({
+        event: event1,
+        session: expect.objectContaining({ id: 'any:1', platform: 'any' }),
+      })
+    );
+    expect(connector.createContext).toBeCalledWith(
+      expect.objectContaining({
+        event: event2,
+        session: expect.objectContaining({ id: 'any:2', platform: 'any' }),
+      })
+    );
+
+    expect(connector.updateSession).toBeCalledWith(expect.any(Object), body);
+    expect(connector.updateSession).toBeCalledWith(expect.any(Object), body);
+
+    expect(sessionStore.write).toBeCalledWith('any:1', {
+      id: 'any:1',
+      platform: 'any',
+      lastActivity: expect.any(Number),
+    });
+    expect(sessionStore.write).toBeCalledWith('any:2', {
+      id: 'any:2',
+      platform: 'any',
+      lastActivity: expect.any(Number),
+    });
+  });
 });
 
 describe('#use', () => {
@@ -361,7 +413,6 @@ describe('#use', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => ({ event, session: undefined })),
@@ -377,7 +428,6 @@ describe('#use', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => ({ event, session: undefined })),
@@ -411,7 +461,6 @@ describe('#onEvent', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => ({ event, session: undefined })),
@@ -429,7 +478,6 @@ describe('#onError', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: ({ emitter }) =>
@@ -468,7 +516,6 @@ describe('#onError', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => ({ event, session: undefined })),
@@ -486,7 +533,6 @@ describe('#setInitialState', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => ({ event, session: undefined })),
@@ -502,7 +548,6 @@ describe('#setInitialState', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => ({ event, session: undefined })),
@@ -545,7 +590,6 @@ describe('request context', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => ({ event, session: undefined })),
@@ -578,7 +622,6 @@ describe('context lifecycle', () => {
     const connector = {
       platform: 'any',
       getUniqueSessionKey: jest.fn(),
-      shouldSessionUpdate: jest.fn(),
       updateSession: jest.fn(),
       mapRequestToEvents: jest.fn(() => [event]),
       createContext: jest.fn(() => ({
diff --git a/packages/bottender/src/line/LineConnector.ts b/packages/bottender/src/line/LineConnector.ts
index 62e5492a5..a52d8a9ed 100644
--- a/packages/bottender/src/line/LineConnector.ts
+++ b/packages/bottender/src/line/LineConnector.ts
@@ -113,8 +113,14 @@ export default class LineConnector
     return this._client;
   }
 
-  getUniqueSessionKey(body: LineRequestBody): string {
-    const { source } = body.events[0];
+  getUniqueSessionKey(bodyOrEvent: LineRequestBody | LineEvent): string {
+    const rawEvent =
+      bodyOrEvent instanceof LineEvent
+        ? bodyOrEvent.rawEvent
+        : bodyOrEvent.events[0];
+
+    const { source } = rawEvent;
+
     if (source.type === 'user') {
       return source.userId;
     }
@@ -129,8 +135,16 @@ export default class LineConnector
     );
   }
 
-  async updateSession(session: Session, body: LineRequestBody): Promise<void> {
-    const { source } = body.events[0];
+  async updateSession(
+    session: Session,
+    bodyOrEvent: LineRequestBody | LineEvent
+  ): Promise<void> {
+    const rawEvent =
+      bodyOrEvent instanceof LineEvent
+        ? bodyOrEvent.rawEvent
+        : bodyOrEvent.events[0];
+
+    const { source } = rawEvent;
 
     if (!session.type) {
       session.type = source.type;
diff --git a/packages/bottender/src/line/__tests__/LineConnector.spec.ts b/packages/bottender/src/line/__tests__/LineConnector.spec.ts
index 8f64f043c..e3bd0cf42 100644
--- a/packages/bottender/src/line/__tests__/LineConnector.spec.ts
+++ b/packages/bottender/src/line/__tests__/LineConnector.spec.ts
@@ -131,7 +131,7 @@ describe('#getUniqueSessionKey', () => {
     expect(senderId).toBe('U206d25c2ea6bd87c17655609a1c37cb8');
   });
 
-  it('extract groupId from user source', () => {
+  it('extract groupId from group source', () => {
     const { connector } = setup();
     const senderId = connector.getUniqueSessionKey({
       events: [
@@ -154,7 +154,7 @@ describe('#getUniqueSessionKey', () => {
     expect(senderId).toBe('U206d25c2ea6bd87c17655609a1c37cb8');
   });
 
-  it('extract roomId from user source', () => {
+  it('extract roomId from room source', () => {
     const { connector } = setup();
     const senderId = connector.getUniqueSessionKey({
       events: [
@@ -177,6 +177,27 @@ describe('#getUniqueSessionKey', () => {
     expect(senderId).toBe('U206d25c2ea6bd87c17655609a1c37cb8');
   });
 
+  it('extract from line event', () => {
+    const { connector } = setup();
+    const senderId = connector.getUniqueSessionKey(
+      new LineEvent({
+        replyToken: 'nHuyWiB7yP5Zw52FIkcQobQuGDXCTA',
+        type: 'message',
+        timestamp: 1462629479859,
+        source: {
+          type: 'user',
+          userId: 'U206d25c2ea6bd87c17655609a1c37cb8',
+        },
+        message: {
+          id: '325708',
+          type: 'text',
+          text: 'Hello, world',
+        },
+      })
+    );
+    expect(senderId).toBe('U206d25c2ea6bd87c17655609a1c37cb8');
+  });
+
   it('should throw error if source.type is not user, group or room', () => {
     const { connector } = setup();
     let error;
diff --git a/packages/bottender/src/messenger/MessengerConnector.ts b/packages/bottender/src/messenger/MessengerConnector.ts
index c2e34e92e..1499d4067 100644
--- a/packages/bottender/src/messenger/MessengerConnector.ts
+++ b/packages/bottender/src/messenger/MessengerConnector.ts
@@ -231,8 +231,13 @@ export default class MessengerConnector
     return this._verifyToken;
   }
 
-  getUniqueSessionKey(body: MessengerRequestBody): string | null {
-    const rawEvent = this._getRawEventsFromRequest(body)[0];
+  getUniqueSessionKey(
+    bodyOrEvent: MessengerRequestBody | MessengerEvent
+  ): string | null {
+    const rawEvent =
+      bodyOrEvent instanceof MessengerEvent
+        ? bodyOrEvent.rawEvent
+        : this._getRawEventsFromRequest(bodyOrEvent)[0];
     if (
       rawEvent &&
       rawEvent.message &&
@@ -249,12 +254,17 @@ export default class MessengerConnector
 
   async updateSession(
     session: Session,
-    body: MessengerRequestBody
+    bodyOrEvent: MessengerRequestBody | MessengerEvent
   ): Promise<void> {
     if (!session.user || this._profilePicExpired(session.user)) {
-      const senderId = this.getUniqueSessionKey(body);
+      const senderId = this.getUniqueSessionKey(bodyOrEvent);
 
-      const rawEvent = this._getRawEventsFromRequest(body)[0];
+      const rawEvent =
+        bodyOrEvent instanceof MessengerEvent
+          ? bodyOrEvent.rawEvent
+          : this._getRawEventsFromRequest(bodyOrEvent)[0];
+
+      // TODO: use this info from event
       const pageId = this._getPageIdFromRawEvent(rawEvent);
       let customAccessToken;
 
diff --git a/packages/bottender/src/messenger/__tests__/MessengerConnector.spec.ts b/packages/bottender/src/messenger/__tests__/MessengerConnector.spec.ts
index 04c715fcc..e916bad14 100644
--- a/packages/bottender/src/messenger/__tests__/MessengerConnector.spec.ts
+++ b/packages/bottender/src/messenger/__tests__/MessengerConnector.spec.ts
@@ -260,6 +260,27 @@ describe('#getUniqueSessionKey', () => {
     const senderId = connector.getUniqueSessionKey(webhookTestRequest.body);
     expect(senderId).toBe(null);
   });
+
+  it('extract from messenger event', () => {
+    const { connector } = setup();
+    const senderId = connector.getUniqueSessionKey(
+      new MessengerEvent({
+        sender: {
+          id: '1412611362105802',
+        },
+        recipient: {
+          id: '1895382890692545',
+        },
+        timestamp: 1486464322190,
+        message: {
+          mid: 'mid.1486464322190:cb04e5a654',
+          seq: 339979,
+          text: 'text',
+        },
+      })
+    );
+    expect(senderId).toBe('1412611362105802');
+  });
 });
 
 describe('#updateSession', () => {