Restrict API calls. Allow only my mobile app

Question

I want my web server to accept requests that originate only from my mobile app.

Since mobile apps are client apps

Answer 1

Considering that you are deploying an application to a client, the actual answer here is 'not possible'. You can make it difficult for someone to fake an 'official id', but because you do not have control over the system that is making the requests, it could be your application or anything else pretending to be your application.