Answer in Brief
The best place to store sensitive information is within a service component of your Angular application.
Reasoning Behind it
When dealing with data received from the server, it's important to keep in mind that client-side security measures can easily be bypassed by savvy users. Even if you try to hide certain aspects of your application, users can still access all the code on the client side.
To ensure better security, focus on securing your routes and content on the server side rather than relying solely on client-side measures. While tools like LocalStorage API or custom Angular services can help manage data storage, remember that anything stored on the client side is ultimately accessible to the user.