diff --git a/android/app/src/main/java/de/nicolasklier/livebeat/MainActivity.kt b/android/app/src/main/java/de/nicolasklier/livebeat/MainActivity.kt
index 3c22968..17c26db 100644
--- a/android/app/src/main/java/de/nicolasklier/livebeat/MainActivity.kt
+++ b/android/app/src/main/java/de/nicolasklier/livebeat/MainActivity.kt
@@ -58,7 +58,7 @@ class MainActivity : AppCompatActivity() {
             val response = client.newCall(req).execute()
 
             if (response.code != 200) {
-                Snackbar.make(findViewById<FloatingActionButton>(R.id.fab), "Device isn't registered yet.", Snackbar.LENGTH_SHORT)
+                Snackbar.make(findViewById<FloatingActionButton>(R.id.fab), "Device isn't registered yet. Registering ...", Snackbar.LENGTH_SHORT)
                         .setBackgroundTint(Color.YELLOW)
                         .setTextColor(Color.BLACK)
                         .show()
diff --git a/backend/app.ts b/backend/app.ts
index 0991ddf..7f357d5 100644
--- a/backend/app.ts
+++ b/backend/app.ts
@@ -92,7 +92,7 @@ async function run() {
     /**
      * Database connection
      */
-    mongoose.set('debug', true);
+    //mongoose.set('debug', true);
     const connection = await mongoose.connect(MONGO_URI, { useNewUrlParser: true, useUnifiedTopology: true }).catch((err) => {
         logger.crit("Database connection could not be made: ", err);
         exit(1);
diff --git a/backend/endpoints/phone.ts b/backend/endpoints/phone.ts
index c0c33d8..329c015 100644
--- a/backend/endpoints/phone.ts
+++ b/backend/endpoints/phone.ts
@@ -1,9 +1,11 @@
 import { Response } from "express";
-import { logger } from "../app";
+import { logger, rabbitmq } from "../app";
 import { LivebeatRequest } from "../lib/request";
 import { Beat } from "../models/beat/beat.model.";
 import { Phone } from "../models/phone/phone.model";
 
+
+
 export async function GetPhone(req: LivebeatRequest, res: Response) {
     const phoneId: String = req.params['id'];
 
@@ -16,7 +18,7 @@ export async function GetPhone(req: LivebeatRequest, res: Response) {
 
     // Check database for phone
     const phone = await Phone.findOne({ androidId: phoneId, user: req.user?._id });
-    if (phone === undefined) {
+    if (phone === null) {
         res.status(404).send();
         return;
     }
@@ -53,7 +55,7 @@ export async function PostPhone(req: LivebeatRequest, res: Response) {
     }
     
     // Create phone
-    await Phone.create({
+    const newPhone = await Phone.create({
         androidId,
         displayName,
         modelName,
@@ -63,7 +65,8 @@ export async function PostPhone(req: LivebeatRequest, res: Response) {
         active: false
     });
 
-    logger.info(`New device (${displayName}) registered for ${req.user?.name}.`)
+    logger.info(`New device (${displayName}) registered for ${req.user?.name}.`);
+    rabbitmq.publish(req.user?.id, newPhone.toJSON(), 'phone_register')
 
     res.status(200).send();
 }
\ No newline at end of file
diff --git a/backend/endpoints/user.ts b/backend/endpoints/user.ts
index bf831d1..f91156a 100644
--- a/backend/endpoints/user.ts
+++ b/backend/endpoints/user.ts
@@ -232,7 +232,7 @@ export async function Resource(req: Request, res: Response) {
         return;
     }
 
-    // TODO: This has to change if we want to allow users to see the realtime movement of others.
+    // TODO: This has to change if we want to allow users to see the realtime movement of others. 
     if (resource.toString().startsWith('tracker-') && resource != 'tracker-' + username) {
         res.status(200).send('deny');
         return;
@@ -242,6 +242,34 @@ export async function Resource(req: Request, res: Response) {
 }
 
 export async function Topic(req: Request, res: Response) {
+    res.status(200);
+
+    const username = req.query.username;
+    const routingKey = req.query.routing_key;
+
+    if (routingKey === undefined || username === undefined) {
+        res.send('deny');
+        return;
+    }
+
+    // Check if it's us
+    if (username.toString() == 'backend') {
+        res.status(200).send('allow');
+        return;
+    }
+
+    // Check if user exists
+    const user = await User.findOne({ name: username.toString() });
+    if (user === null) {
+        res.send('deny');
+        return;
+    }
+
+    if (routingKey !== user.id) {
+        res.send('deny');
+        return;
+    }
+
     res.status(200).send('allow');
 }
 
diff --git a/backend/lib/rabbit.ts b/backend/lib/rabbit.ts
index 0807b0b..aae137c 100644
--- a/backend/lib/rabbit.ts
+++ b/backend/lib/rabbit.ts
@@ -14,6 +14,8 @@ export class RabbitMQ {
     connection: amqp.Connection | null = null;
     channel: amqp.Channel | null = null;
 
+    timeouts: Map<string, Timeout> = new Map<string, Timeout>();
+
     async init() {
         this.connection = await amqp.connect(RABBITMQ_URI);
         this.channel = await this.connection.createChannel();
@@ -26,7 +28,7 @@ export class RabbitMQ {
             // Get phone
             const phone = await Phone.findOne({ androidId: msg.token });
             if (phone == undefined) {
-                logger.info(`Received beat from unknown device with id ${msg.token}`);
+                logger.warning(`Received beat from unknown device with id ${msg.token}`);
                 return;
             }
 
@@ -41,13 +43,33 @@ export class RabbitMQ {
                 battery: msg.battery,
                 createdAt: msg.timestamp
             });
+
+            // Broadcast if device became active
+            if (this.timeouts.has(phone.id)) {
+                clearTimeout(this.timeouts.get(phone.id));
+            } else {
+                logger.debug('Set phone active');
+                phone.active = true;
+                await phone.save();
+                this.publish(phone.user.toString(), phone.toJSON(), 'phone_alive');
+            }
+
+            const timeoutTimer = setTimeout(async () => {
+                this.publish(phone.user.toString(), phone.toJSON(), 'phone_dead');
+                this.timeouts.delete(phone.id);
+                phone.active = false;
+                await phone.save();
+            }, 30_000);
+            this.timeouts.set(phone.id, timeoutTimer);
             
-            this.channel!.publish('amq.topic', '.', Buffer.from(JSON.stringify(newBeat.toJSON())));
+            this.publish(phone.user.toString(), newBeat.toJSON(), 'beat');
         }, { noAck: true });
     }
 
-    async publish(queueName = 'tracker', data: any) {
+    async publish(userId: string, data: any, type: 'beat' | 'phone_alive' | 'phone_dead' | 'phone_register' | 'panic' = 'beat') {
         if (this.connection == undefined) await this.init()
-        this.channel?.sendToQueue(queueName, Buffer.from(data));
+
+        data = { type, ...data };
+        this.channel?.publish('amq.topic', userId, Buffer.from(JSON.stringify(data)));
     }
 }
\ No newline at end of file
diff --git a/frontend/src/app/_alert/alert.service.ts b/frontend/src/app/_alert/alert.service.ts
index f33641c..b97656e 100644
--- a/frontend/src/app/_alert/alert.service.ts
+++ b/frontend/src/app/_alert/alert.service.ts
@@ -6,6 +6,7 @@ export class Alert {
   type: AlertType;
   message: string;
   title?: string;
+  onClick?: () => void;
   duration = 5;
   isClosing = false;
 
@@ -26,6 +27,8 @@ export class AlertService {
     private subject = new Subject<Alert>();
     private defaultId = 'default-alert';
 
+    private errorSoundPath = 'assets/sounds/error.mp3';
+
     // enable subscribing to alerts observable
     onAlert(id = this.defaultId): Observable<Alert> {
         return this.subject.asObservable();
@@ -37,6 +40,10 @@ export class AlertService {
     }
 
     error(message: string, title = 'Error!', options?: any): void {
+        const audio = new Audio(this.errorSoundPath);
+        audio.load();
+        audio.play();
+
         this.alert(new Alert({ ...options, type: AlertType.Error, message, title }));
     }
 
diff --git a/frontend/src/app/_alert/alert/alert.component.html b/frontend/src/app/_alert/alert/alert.component.html
index 465c6bb..5789ee3 100644
--- a/frontend/src/app/_alert/alert/alert.component.html
+++ b/frontend/src/app/_alert/alert/alert.component.html
@@ -1,4 +1,4 @@
-<div [ngClass]="cssClass(alert)" *ngFor="let alert of this.alerts">
+<div [ngClass]="cssClass(alert)" *ngFor="let alert of this.alerts" (click)="alert.onClick()">
     <span class="title">{{alert.title}}</span>
     <span class="message">{{alert.message}}</span>
     <fa-icon [icon]="faClose" (click)="removeAlert(alert)"></fa-icon>
diff --git a/frontend/src/app/_alert/alert/alert.component.scss b/frontend/src/app/_alert/alert/alert.component.scss
index 96901a5..b8867ee 100644
--- a/frontend/src/app/_alert/alert/alert.component.scss
+++ b/frontend/src/app/_alert/alert/alert.component.scss
@@ -20,6 +20,7 @@
     vertical-align: middle;
     transition: 0.25s ease;
     animation: appear 0.5s ease;
+    cursor: pointer;
 
     box-shadow:
         0 4.5px 5.3px rgba(0, 0, 0, 0.121),
@@ -56,6 +57,7 @@
 
 .alert-warning {
     background-color: #F3CC17 !important;
+    color: #000 !important;
 }
 
 .fadeOut {
diff --git a/frontend/src/app/_alert/alert/alert.component.ts b/frontend/src/app/_alert/alert/alert.component.ts
index f9bed3d..b97757a 100644
--- a/frontend/src/app/_alert/alert/alert.component.ts
+++ b/frontend/src/app/_alert/alert/alert.component.ts
@@ -30,9 +30,11 @@ export class AlertComponent implements OnInit, OnDestroy {
         this.alerts.push(alert);
         this.alerts = this.alerts.reverse();
 
-        setTimeout(() => {
-          this.removeAlert(alert);
-        }, alert.duration * 1000);
+        if (alert.duration !== 0) {
+          setTimeout(() => {
+            this.removeAlert(alert);
+          }, alert.duration * 1000);
+        }
       });
   }
 
@@ -68,6 +70,15 @@ export class AlertComponent implements OnInit, OnDestroy {
 
     classes.push(alertTypeClass[alert.type]);
 
+    // Save the original onClick function.
+    const actualFunction = alert.onClick || null;
+
+    // Override onClick function so that notification disappears after clicked.
+    alert.onClick = () => {
+      if (actualFunction !== null) { actualFunction(); }
+      this.removeAlert(alert);
+    };
+
     if (alert.isClosing) { classes.push('fadeOut'); }
 
     return classes.join(' ');
diff --git a/frontend/src/app/admin/admin.component.html b/frontend/src/app/admin/admin.component.html
index 2a0cf3a..73c4ef2 100644
--- a/frontend/src/app/admin/admin.component.html
+++ b/frontend/src/app/admin/admin.component.html
@@ -1,5 +1,4 @@
 <h2>Create new user</h2>
-<button (click)="alert()">Make info</button>
 <form (ngSubmit)="createUser()" #form="ngForm">
     <input name="username" [(ngModel)]="newUsername" placeholder="Username"><br>
     <input name="password" [(ngModel)]="newPassword" type="password" placeholder="Password"><br>
diff --git a/frontend/src/app/admin/admin.component.ts b/frontend/src/app/admin/admin.component.ts
index d7c39bf..42ce736 100644
--- a/frontend/src/app/admin/admin.component.ts
+++ b/frontend/src/app/admin/admin.component.ts
@@ -1,4 +1,5 @@
 import { AfterContentInit, Component, OnDestroy, OnInit } from '@angular/core';
+import { resolve } from 'dns';
 import { APIService, UserType } from '../api.service';
 import { AlertService } from '../_alert/alert.service';
 
@@ -15,7 +16,7 @@ export class AdminComponent implements AfterContentInit, OnDestroy {
   newType: UserType;
   invitationCode: string;
 
-  constructor(public api: APIService, private alertt: AlertService) { }
+  constructor(public api: APIService, private alert: AlertService) { }
 
   ngAfterContentInit(): void {
     this.api.showFilter = false;
@@ -27,11 +28,17 @@ export class AdminComponent implements AfterContentInit, OnDestroy {
   }
 
   async createUser(): Promise<void> {
-    this.invitationCode = await this.api.createUser(this.newUsername, this.newPassword, this.newType);
-  }
-
-  alert() {
-    this.alertt.info('This is a test from admin', 'Admin says');
+    this.api.createUser(this.newUsername, this.newPassword, this.newType)
+      .catch(error => {
+        if (error.statusCode === 409) {
+          this.alert.error('This user already exists');
+        } else {
+          this.alert.error('There was an error while creating this user');
+        }
+      }).then((val: string) => {
+        this.invitationCode = val;
+        this.alert.success(`User ${this.newUsername} created.`, 'Created');
+      });
   }
 
 }
diff --git a/frontend/src/app/api.service.ts b/frontend/src/app/api.service.ts
index 042a159..ba25742 100644
--- a/frontend/src/app/api.service.ts
+++ b/frontend/src/app/api.service.ts
@@ -4,6 +4,7 @@ import { MqttService } from 'ngx-mqtt';
 import { BehaviorSubject } from 'rxjs';
 import * as moment from 'moment';
 import { error } from 'protractor';
+import { AlertService } from './_alert/alert.service';
 
 export interface ILogin {
   token: string;
@@ -107,7 +108,7 @@ export class APIService {
 
   API_ENDPOINT = 'http://192.168.178.26:8040';
 
-  constructor(private httpClient: HttpClient, private mqtt: MqttService) { }
+  constructor(private httpClient: HttpClient, private mqtt: MqttService, private alert: AlertService) { }
 
   private mqttInit(): void {
     // Connect with RabbitMQ after we received our user information
@@ -120,12 +121,31 @@ export class APIService {
       password: this.user.brokerToken
     });
 
-    this.mqtt.observe('/').subscribe(message => {
-      if (this.beats !== undefined) {
-        const obj = JSON.parse(message.payload.toString()) as IBeat;
-        this.beats.push(obj);
-        this.beatsEvent.next([obj]);  // We just push one, so all the map doesn't has to rebuild the entire map.
-        this.beatStats.totalBeats++;
+    this.mqtt.observe(this.user._id).subscribe(message => {
+      if (message !== undefined || message !== null) {
+        const obj = JSON.parse(message.payload.toString());
+
+        switch (obj.type) {
+          case 'beat':
+            if (this.beats !== undefined) {
+              this.beats.push(obj);
+              this.beatsEvent.next([obj]);  // We just push one, so the map doesn't has to rebuild everything from scratch.
+              this.beatStats.totalBeats++;
+            }
+            break;
+          case 'phone_available':
+            this.alert.info(`Device ${obj.name} is now online`, 'Device');
+            break;
+          case 'phone_register':
+            this.alert.success(`New device "${obj.displayName}"`, 'New device');
+            break;
+          case 'phone_alive':
+            this.alert.info('Device is now active', obj.displayName.toString());
+            break;
+          case 'phone_dead':
+            this.alert.warn('Device is now offline', obj.displayName.toString());
+            break;
+        }
       }
     });
   }
@@ -149,6 +169,7 @@ export class APIService {
           await this.getBeats();
           await this.getBeatStats();
           this.loginEvent.next(true);
+          this.alert.success('Login successful', 'Login', { duration: 2 });
           resolve(token as ILogin);
         });
     });
@@ -175,8 +196,11 @@ export class APIService {
         .subscribe((res: any) => {
           this.fetchingDataEvent.next(false);
           console.log('Response:', res);
-          
+
           resolve(res.setupToken);
+        },
+        error => {
+          reject(error);
         });
     });
   }
@@ -331,6 +355,16 @@ export class APIService {
     return earthRadiusKm * c;
   }
 
+  /**
+   * Looks if certain unique objects are present in provided object `obj`.
+   *
+   * If yes, it's a beat (true)
+   * @param obj Object where you think it could be a beat.
+   */
+  isBeatObject(obj: any): boolean {
+    return (obj._id instanceof String && obj.battery instanceof Number && obj.accuracy instanceof Number);
+  }
+
   /**
    * Short form for `this.api.beats[this.api.beats.length - 1]`
    *
diff --git a/frontend/src/app/app.component.html b/frontend/src/app/app.component.html
index 6a3aee8..f5377f9 100644
--- a/frontend/src/app/app.component.html
+++ b/frontend/src/app/app.component.html
@@ -2,10 +2,18 @@
 
 <div id="header" *ngIf="this.api.loginEvent.value">
   <ul class="navbar">
-    <li><a [routerLink]="['/dashboard']" routerLinkActive="router-link-active" >Dashboard</a></li>
-    <li><a [routerLink]="['/map']" routerLinkActive="router-link-active" >Map</a></li>
-    <li class="navbar-right"><a [routerLink]="['/user', this.api.user._id]" routerLinkActive="router-link-active" >{{this.api.username}}</a></li>
-    <li class="navbar-right"><a [routerLink]="['/admin']" routerLinkActive="router-link-active" *ngIf="this.api.user.type == 'admin'">Admin settings</a></li>
+    <li><a [routerLink]="['/dashboard']" routerLinkActive="router-link-active">Dashboard</a></li>
+    <li><a [routerLink]="['/map']" routerLinkActive="router-link-active">Map</a></li>
+
+    <li class="navbar-right"><a [routerLink]="['/user', this.api.user._id]"
+        routerLinkActive="router-link-active">
+        <fa-icon [icon]="faUser"></fa-icon>
+        {{this.api.username}}</a></li>
+
+    <li class="navbar-right"><a [routerLink]="['/admin']" routerLinkActive="router-link-active"
+        *ngIf="this.api.user.type == 'admin'">
+        Admin settings</a>
+    </li>
   </ul>
 </div>
 <div class="header-spacer"></div>
diff --git a/frontend/src/app/app.component.ts b/frontend/src/app/app.component.ts
index ac61896..203dea1 100644
--- a/frontend/src/app/app.component.ts
+++ b/frontend/src/app/app.component.ts
@@ -1,4 +1,5 @@
 import { Component, OnInit } from '@angular/core';
+import { faUser } from '@fortawesome/free-solid-svg-icons';
 import { APIService } from './api.service';
 import { AlertService } from './_alert/alert.service';
 
@@ -11,6 +12,7 @@ export class AppComponent implements OnInit{
   title = 'Livebeat';
 
   showOverlay = false;
+  faUser = faUser;
 
   constructor(public api: APIService, private alert: AlertService) {
     this.api.fetchingDataEvent.subscribe(status => {
@@ -20,8 +22,7 @@ export class AppComponent implements OnInit{
 
   async ngOnInit(): Promise<void> {
     await this.api.login('admin', '$1KDaNCDlyXAOg');
-    this.alert.success('This is just a test', 'Test');
-    this.alert.error('Requested user doesn\'t exist', 'Not found');
+    this.alert.error('Audio test');
     return;
   }
 }
diff --git a/frontend/src/app/dashboard/dashboard.component.ts b/frontend/src/app/dashboard/dashboard.component.ts
index bb27155..f22a84f 100644
--- a/frontend/src/app/dashboard/dashboard.component.ts
+++ b/frontend/src/app/dashboard/dashboard.component.ts
@@ -58,7 +58,7 @@ export class DashboardComponent implements AfterViewInit {
 
     this.api.beatsEvent.subscribe(beats => {
       // Only reset array if this is not an update.
-      if (beats.length !== 1) {
+      if (beats.length > 1) {
         this.batteryLineChartData[0].data = [];
         this.batteryLineChartLabels = [];
       }
diff --git a/frontend/src/app/map/map.component.ts b/frontend/src/app/map/map.component.ts
index 9aae1c5..875b65a 100644
--- a/frontend/src/app/map/map.component.ts
+++ b/frontend/src/app/map/map.component.ts
@@ -159,8 +159,6 @@ export class MapComponent {
   }
 
   buildMap(isUpdate: boolean, maxAccuracy: number = 30): void {
-    console.log(isUpdate);
-
     // If this is an update don't rebuild entire map.
     if (!isUpdate) {
       if (this.api.beats.length === 0) {
diff --git a/frontend/src/app/user/user.component.html b/frontend/src/app/user/user.component.html
index c7b5454..9fbed77 100644
--- a/frontend/src/app/user/user.component.html
+++ b/frontend/src/app/user/user.component.html
@@ -7,7 +7,7 @@
     <h2 *ngIf="showDevices">Devices</h2>
     <ul class="phoneListing" *ngIf="showDevices">
         <li *ngFor="let phone of this.api.phones">
-            <h2>{{phone.displayName}} <span class="lastBeat">last beat was {{ this.lastBeats.get(phone._id) }}</span></h2>
+            <h2 [ngClass]="{offline: !phone.active}">{{phone.displayName}} <span class="lastBeat">last beat was {{ this.lastBeats.get(phone._id) }}</span></h2>
             <p>{{phone.modelName}}</p>
         </li>
     </ul>
diff --git a/frontend/src/app/user/user.component.scss b/frontend/src/app/user/user.component.scss
index e6a7b18..2f47512 100644
--- a/frontend/src/app/user/user.component.scss
+++ b/frontend/src/app/user/user.component.scss
@@ -25,6 +25,10 @@
     background-color: $darker;
 }
 
+.offline {
+    color: #ff6464
+}
+
 .lastBeat {
     font-weight: lighter;
     font-size: 10pt;
diff --git a/frontend/src/app/user/user.component.ts b/frontend/src/app/user/user.component.ts
index 8dd65a9..72a6898 100644
--- a/frontend/src/app/user/user.component.ts
+++ b/frontend/src/app/user/user.component.ts
@@ -8,7 +8,7 @@ import { ActivatedRoute } from '@angular/router';
   templateUrl: './user.component.html',
   styleUrls: ['./user.component.scss']
 })
-export class UserComponent implements AfterContentInit, OnDestroy {
+export class UserComponent implements AfterContentInit, OnDestroy, OnInit {
 
   lastLogin: string;
   lastBeats: Map<string, string> = new Map<string, string>();
@@ -60,7 +60,12 @@ export class UserComponent implements AfterContentInit, OnDestroy {
 
   ngAfterContentInit(): void {
     this.api.showFilter = false;
-    console.log(this.api.showFilter);
+  }
+
+  ngOnInit(): void {
+    if (this.api.hasSession()) {
+      this.api.getPhones();
+    }
   }
 
   ngOnDestroy(): void {
diff --git a/frontend/src/assets/sounds/error.mp3 b/frontend/src/assets/sounds/error.mp3
new file mode 100644
index 0000000..17ea1c6
Binary files /dev/null and b/frontend/src/assets/sounds/error.mp3 differ