diff --git a/src/consts/channel_names.ts b/src/consts/channel_names.ts
index 55250cf..789d501 100644
--- a/src/consts/channel_names.ts
+++ b/src/consts/channel_names.ts
@@ -7,4 +7,5 @@ export const channel_on_game_end = "on_game_end"
 export const channel_on_game_crashed = "on_game_crashed"
 export const channel_on_game_user_leave = "on_game_user_leave"
 export const channel_ping = "ping"
-export const channel_pong = "pong"
\ No newline at end of file
+export const channel_pong = "pong"
+export const channel_on_user_connection_change = "channel_on_user_connection_change"
\ No newline at end of file
diff --git a/src/game/GameManager.ts b/src/game/GameManager.ts
index a604419..f3bc1a8 100644
--- a/src/game/GameManager.ts
+++ b/src/game/GameManager.ts
@@ -9,17 +9,19 @@ import {
     channel_on_game_crashed,
     channel_on_game_start,
     channel_on_game_update,
-    channel_on_game_user_leave
+    channel_on_game_user_leave,
+    channel_on_user_connection_change
 } from "../consts/channel_names";
 import { GameMove } from "../models/GameMove";
 import { GameCrashManager } from "./GameCrashManager";
 import { MatchMaker } from "../matchmaker/MatchMaker";
+import { UserConnectionInfo } from "../models/UserConnectionInfo";
 
 export class GameManager {
     gameStore: GameStore;
     rtmt: RTMT;
     matchMaker: MatchMaker;
-    
+
     constructor(params: { gameStore: GameStore, rtmt: RTMT, matchMaker: MatchMaker }) {
         this.gameStore = params.gameStore;
         this.rtmt = params.rtmt;
@@ -30,6 +32,7 @@ export class GameManager {
     private initialize() {
         this.listenOnPlayersPaired();
         this.listenRtmtMessages();
+        this.listenUserConnectionChange();
     }
 
     private listenRtmtMessages() {
@@ -43,7 +46,7 @@ export class GameManager {
 
         this.rtmt.listenMessage(channel_leave_game, (userKey: string, message: Object) => {
             this.onPlayerLeave(userKey)
-        });        
+        });
     }
 
     private onGameMove(userKey: string, gameMove: GameMove) {
@@ -108,6 +111,16 @@ export class GameManager {
     public startGame(game: MancalaGame) {
         this.rtmt.sendMessage(game.player1Id, channel_on_game_start, game);
         this.rtmt.sendMessage(game.player2Id, channel_on_game_start, game);
+        this.sendUserConnectionInfo(game, game.player1Id);
+        this.sendUserConnectionInfo(game, game.player2Id);
+    }
+
+    public sendUserConnectionInfo(game: MancalaGame, playerId: string, isOnline?: boolean) {
+        //todo: reimplement when watch game feature added
+        const _isOnline = isOnline === undefined ? this.rtmt.isClientOnline(playerId) : isOnline;
+        const otherUser = game.player1Id === playerId ? game.player2Id : game.player1Id;
+        const userConnectionInfo: UserConnectionInfo = { userId: playerId, isOnline: _isOnline };
+        this.rtmt.sendMessage(otherUser, channel_on_user_connection_change, userConnectionInfo);
     }
 
     public deleteGame(game: MancalaGame) {
@@ -116,4 +129,17 @@ export class GameManager {
             this.gameStore.remove(game.player2Id);
         }
     }
+
+    private listenUserConnectionChange() {
+        this.rtmt.listenOnClientConnectionChange((clientId: string, isOnline: boolean) => {
+            const game = this.gameStore.get(clientId);
+            if (game) {
+                this.sendUserConnectionInfo(game, clientId, isOnline);
+                if (isOnline) {
+                    const otherUser = game.player1Id === clientId ? game.player2Id : game.player1Id;
+                    this.sendUserConnectionInfo(game, otherUser);
+                }
+            }
+        });
+    }
 }
\ No newline at end of file
diff --git a/src/models/User.ts b/src/models/User.ts
new file mode 100644
index 0000000..e5ab1ae
--- /dev/null
+++ b/src/models/User.ts
@@ -0,0 +1,6 @@
+export interface User {
+    id: string;
+    name: string;
+    isOnline: boolean;
+    isAnonymous: boolean;
+}
\ No newline at end of file
diff --git a/src/models/UserConnectionInfo.ts b/src/models/UserConnectionInfo.ts
new file mode 100644
index 0000000..3ce426f
--- /dev/null
+++ b/src/models/UserConnectionInfo.ts
@@ -0,0 +1,4 @@
+export interface UserConnectionInfo {
+    userId: string;
+    isOnline: boolean;
+}
\ No newline at end of file
diff --git a/src/rtmt/rtmt.ts b/src/rtmt/rtmt.ts
index aa8ccdf..238cad0 100644
--- a/src/rtmt/rtmt.ts
+++ b/src/rtmt/rtmt.ts
@@ -1,8 +1,10 @@
 export type Bytes = Buffer
 export type OnMessage = (clientID: string, message: Object) => any
+export type OnClientConnectionChange = (clientID: string, isOnline : boolean) => any
 
 export interface RTMT {
     sendMessage: (clientID: string, channel: string, message: Object) => any;
     listenMessage: (channel: string, callback: OnMessage) => any;
     isClientOnline(clientID: string): boolean;
+    listenOnClientConnectionChange(onUserConnectionChange: OnClientConnectionChange): void;
 }
\ No newline at end of file
diff --git a/src/rtmt/rtmt_websocket.ts b/src/rtmt/rtmt_websocket.ts
index 45d8529..5f63494 100644
--- a/src/rtmt/rtmt_websocket.ts
+++ b/src/rtmt/rtmt_websocket.ts
@@ -1,5 +1,5 @@
 import { decode, encode } from "./encode_decode_message"
-import { Bytes, OnMessage, RTMT } from "./rtmt"
+import { Bytes, OnClientConnectionChange, OnMessage, RTMT } from "./rtmt"
 
 import WebSocket from "ws"
 import * as http from 'http';
@@ -17,6 +17,8 @@ export class RTMTWS implements RTMT {
 
     private pingInterval?: NodeJS.Timeout = undefined;
 
+    onUserConnectionChange?: OnClientConnectionChange;
+
     constructor() {
         this.messageChannels = new Map<String, OnMessage>()
         this.wsServer = null
@@ -32,6 +34,7 @@ export class RTMTWS implements RTMT {
             const regexResult = req.url.split(RegExp("\/\?userKey="));
             const clientID = regexResult[1]
             this.clients.set(clientID, ws)
+            this.onUserConnectionChange?.(clientID, true);
             ws.on("message", (messageBytes: string) => {
                 this.onWebSocketMessage(clientID, messageBytes)
             })
@@ -39,6 +42,7 @@ export class RTMTWS implements RTMT {
             ws.on("close", (code: number, reason: string) => {
                 console.log("WS Closed! code : " + code + " reason : " + reason);
                 this.clients.delete(clientID)
+                this.onUserConnectionChange?.(clientID, false);
             })
 
             ws.on("error", (err: Error) => {
@@ -130,4 +134,8 @@ export class RTMTWS implements RTMT {
     isClientOnline(clientID: string): boolean {
         return this.clients.has(clientID);
     }
+
+    listenOnClientConnectionChange(onUserConnectionChange: OnClientConnectionChange) {
+        this.onUserConnectionChange = onUserConnectionChange;
+    }
 }
\ No newline at end of file