There are a few steps to update an Angular application to the latest version:

1. Make sure you have the latest Angular CLI installed. You can install it with:

npm install -g @angular/cli@latest

1. Update your Angular dependencies to the latest version. You'll need to update @angular/core, @angular/cli, and any other Angular libraries your app uses.

For example, to update to Angular 12, you would run:

ng update @angular/core@12 @angular/cli@12

1. Run ng update to update the Angular configuration files like angular.json.

ng update @angular/cli

1. Update any third-party dependencies to compatible versions. Some libraries may require version updates when updating Angular.

2. Make any necessary code changes. The Angular Update Guide can help identify any changes needed for your app.

3. Build and serve your application to test for any errors. Resolve any build errors or warnings.

ng build
ng serve

1. If needed, update from HttpModule to HttpClientModule and switch to pipeable RxJS operators.

Some other tips:

• Update to the latest Angular version as soon as possible to minimize required code changes.

• Keep a watch on deprecated features and plan changes ahead of time.

• Use the --force and --allow-dirty flags with ng update if needed.

Hope this helps! Let me know if you have any other questions.