diff --git a/api/src/main/java/com/rossa/api/controllers/AppContoller.java b/api/src/main/java/com/rossa/api/controllers/AppContoller.java
index b1f6515..e454f84 100644
--- a/api/src/main/java/com/rossa/api/controllers/AppContoller.java
+++ b/api/src/main/java/com/rossa/api/controllers/AppContoller.java
@@ -1,16 +1,22 @@
-// package com.rossa.api.controllers;
+package com.rossa.api.controllers;
 
-// import org.springframework.stereotype.Controller;
-// import org.springframework.web.bind.annotation.RequestMapping;
-// import org.springframework.web.bind.annotation.RequestMethod;
-// import org.springframework.web.servlet.ModelAndView;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.http.MediaType;
+import org.springframework.security.access.prepost.PreAuthorize;
 
-// @Controller
-// public class AppContoller {
-// @RequestMapping(value = "/public/index", method = RequestMethod.GET)
-// public ModelAndView index() {
-// ModelAndView retVal = new ModelAndView();
-// retVal.setViewName("indexPage");
-// return retVal;
-// }
-// }
\ No newline at end of file
+@RestController
+@PreAuthorize("isAuthenticated()")
+public class AppContoller {
+
+    @Value("${rossatech.api.version}")
+    private String apiVersion;
+
+    @RequestMapping(value = "/version", method = RequestMethod.GET, produces = MediaType.TEXT_PLAIN_VALUE)
+    public String getApiVersion() {
+        return apiVersion;
+    }
+
+}
\ No newline at end of file
diff --git a/api/src/main/resources/application.properties b/api/src/main/resources/application.properties
index 394a391..cee1bf7 100644
--- a/api/src/main/resources/application.properties
+++ b/api/src/main/resources/application.properties
@@ -18,4 +18,7 @@ spring.jackson.serialization.fail-on-empty-beans=false
 
 # spring.security.user.name=pezi
 # spring.security.user.password=Password123!
-security.basic.enabled=false
\ No newline at end of file
+security.basic.enabled=false
+
+#api version
+rossatech.api.version=0.2
\ No newline at end of file
diff --git a/rossa-tech webpage.txt b/rossa-tech webpage.txt
index 3d3f741..d92d5ce 100644
--- a/rossa-tech webpage.txt	
+++ b/rossa-tech webpage.txt	
@@ -1,3 +1,8 @@
+INSTALL MAVEN: https://mkyong.com/maven/how-to-install-maven-in-windows/
+
+build API: mvn package // oder mvn clean package?!?
+
+
 - login (simple)
     ? - https://www.bezkoder.com/angular-12-jwt-auth/
     ? - https://martinelli.ch/angular-15-spring-boot-3-and-jwt/
diff --git a/rossa-tech-cli/src/app/components/footer/footer.component.html b/rossa-tech-cli/src/app/components/footer/footer.component.html
index d48fb98..660e7ee 100644
--- a/rossa-tech-cli/src/app/components/footer/footer.component.html
+++ b/rossa-tech-cli/src/app/components/footer/footer.component.html
@@ -1,8 +1,18 @@
 <div class="footer-wrapper" *ngIf="userLoggedIn">
     <div class="version-web" *ngIf="versionWeb">
-        Web: v{{versionWeb}}
+        <span class="label">
+            Web:
+        </span>
+        <span class="version">
+            v.{{versionWeb}}
+        </span>
     </div>
     <div class="version-api" *ngIf="versionApi">
-        API: v{{versionApi}}
+        <span class="label">
+            API:
+        </span>
+        <span class="version">
+            v.{{versionApi}}
+        </span>
     </div>
 </div>
\ No newline at end of file
diff --git a/rossa-tech-cli/src/app/components/footer/footer.component.scss b/rossa-tech-cli/src/app/components/footer/footer.component.scss
index 2d55ffa..bd74b8f 100644
--- a/rossa-tech-cli/src/app/components/footer/footer.component.scss
+++ b/rossa-tech-cli/src/app/components/footer/footer.component.scss
@@ -5,4 +5,17 @@ div.footer-wrapper {
   justify-content: flex-end;
   padding-right: 16px;
   align-items: center;
+
+  div.version-api {
+    margin-left: 16px;
+  }
+  span.version {
+    font-size: 12px;
+    font-style: italic;
+  }
+
+  span.label {
+    font-size: 12px;
+    font-weight: bold;
+  }
 }
diff --git a/rossa-tech-cli/src/app/components/footer/footer.component.ts b/rossa-tech-cli/src/app/components/footer/footer.component.ts
index 5e3beaa..05a47df 100644
--- a/rossa-tech-cli/src/app/components/footer/footer.component.ts
+++ b/rossa-tech-cli/src/app/components/footer/footer.component.ts
@@ -4,6 +4,7 @@ import { HttpErrorResponse } from '@angular/common/http';
 import { LoaderService } from '../loader/loader.service';
 import { environment } from 'src/environments/environment';
 import { AuthService } from 'src/app/auth/auth.service';
+import { DatabaseService } from 'src/app/core/services/database.service';
 
 @Component({
   selector: 'app-footer',
@@ -14,11 +15,12 @@ import { AuthService } from 'src/app/auth/auth.service';
 })
 export class FooterComponent implements OnInit {
   versionWeb: number | undefined = environment.version;
-  versionApi: number | undefined;
+  versionApi: string | undefined;
   userLoggedIn: Boolean = false;
 
   //injects
   private authService: AuthService = inject(AuthService);
+  private databaseService: DatabaseService = inject(DatabaseService);
   // private loaderService: LoaderService = inject(LoaderService);
 
   constructor() {}
@@ -27,5 +29,18 @@ export class FooterComponent implements OnInit {
     this.authService.isLoggedIn.subscribe((res) => {
       this.userLoggedIn = res;
     });
+    this.getApiVersion();
+
+    if (this.userLoggedIn) {
+      this.databaseService.getApiVersion();
+    }
+  }
+
+  getApiVersion(): void {
+    this.databaseService.apiVersion.subscribe({
+      next: (value) => {
+        this.versionApi = value;
+      },
+    });
   }
 }
diff --git a/rossa-tech-cli/src/app/components/loginPage/login.component.ts b/rossa-tech-cli/src/app/components/loginPage/login.component.ts
index f27369b..a65c9c4 100644
--- a/rossa-tech-cli/src/app/components/loginPage/login.component.ts
+++ b/rossa-tech-cli/src/app/components/loginPage/login.component.ts
@@ -9,6 +9,7 @@ import { FormControl, FormGroup, Validators } from '@angular/forms';
 import { LoaderService } from '../loader/loader.service';
 import { FormsService } from 'src/app/core/services/forms.service';
 import { NotificationService } from 'src/app/core/services/notification.service';
+import { DatabaseService } from 'src/app/core/services/database.service';
 
 @Component({
   selector: 'app-root',
@@ -29,6 +30,7 @@ export class LoginComponent implements OnInit {
   private notificationService: NotificationService =
     inject(NotificationService);
   private router: Router = inject(Router);
+  private dataBaseService: DatabaseService = inject(DatabaseService);
 
   constructor() {}
 
@@ -65,6 +67,7 @@ export class LoginComponent implements OnInit {
             resp.tokenValue.trim() !== ''
           ) {
             this.loginService.setSessionCurrentUser(resp);
+            this.dataBaseService.getApiVersion();
             this.router.navigate(['/']);
           }
         },
diff --git a/rossa-tech-cli/src/app/core/services/database.service.ts b/rossa-tech-cli/src/app/core/services/database.service.ts
index 3b2d9c7..92bb2d0 100644
--- a/rossa-tech-cli/src/app/core/services/database.service.ts
+++ b/rossa-tech-cli/src/app/core/services/database.service.ts
@@ -4,7 +4,7 @@ import {
   HttpErrorResponse,
   HttpHeaders,
 } from '@angular/common/http';
-import { Observable, throwError } from 'rxjs';
+import { BehaviorSubject, Observable, throwError } from 'rxjs';
 import { catchError } from 'rxjs/operators';
 import { environment } from 'src/environments/environment';
 import { Meter, MeterData } from '../dataModels/Meterdata';
@@ -15,7 +15,13 @@ import { Meter, MeterData } from '../dataModels/Meterdata';
 export class DatabaseService {
   private baseUrl = environment.apiBaseUrl;
 
-  constructor(private http: HttpClient) {}
+  private apiVersionSubject: BehaviorSubject<string> =
+    new BehaviorSubject<string>('');
+  public apiVersion: Observable<string>;
+
+  constructor(private http: HttpClient) {
+    this.apiVersion = this.apiVersionSubject.asObservable();
+  }
 
   getMeterData(): Observable<MeterData[]> {
     const url = `${this.baseUrl}/meter-data`;
@@ -55,4 +61,16 @@ export class DatabaseService {
     // Return an observable with a user-facing error message.
     return throwError(() => error);
   }
+
+  public getApiVersion(): void {
+    const url = `${this.baseUrl}/version`;
+    this.http
+      .get<string>(url)
+      .pipe(catchError(this.handleError))
+      .subscribe({
+        next: (value) => {
+          this.apiVersionSubject.next(value);
+        },
+      });
+  }
 }
diff --git a/rossa-tech-cli/src/environments/environment.prod.ts b/rossa-tech-cli/src/environments/environment.prod.ts
index 48d98eb..e62be09 100644
--- a/rossa-tech-cli/src/environments/environment.prod.ts
+++ b/rossa-tech-cli/src/environments/environment.prod.ts
@@ -2,5 +2,5 @@ export const environment = {
   production: true,
   env: 'prod',
   apiBaseUrl: 'http://192.168.178.21:8182/api',
-  version: 0.2,
+  version: 0.3,
 };
diff --git a/rossa-tech-cli/src/environments/environment.ts b/rossa-tech-cli/src/environments/environment.ts
index f343578..2f31092 100644
--- a/rossa-tech-cli/src/environments/environment.ts
+++ b/rossa-tech-cli/src/environments/environment.ts
@@ -6,7 +6,7 @@ export const environment = {
   production: false,
   env: 'local',
   apiBaseUrl: 'http://localhost:8080',
-  version: 0.2,
+  version: 0.4,
   // apiBaseUrl: 'http://192.168.178.21:8182/api',
 };