Server side authorization through social networks in a react native mobile application, which flow should be applied?

Question

Mobile development

Good afternoon!
On the Internet, I found this flow:
1. The application opens the authorization dialog inside the application through the in app browser (using implicit)
2. Authorizes, receives a token
3. Sends this token to the server and saves it.
But I don't think this option is safe.
It seems to me that the flow that I have in my head will be more reliable.
Uses the authorization method with an intermediate step where we get the code.
1. The application opens a dialog
2. We get the code
3. We send this code to the server (in order to get an access_token from it, you need to have a secret key, in fact, nothing can be done with this code without it)
4. On the server, using the code and the secret key, we ask already access_token
Why do you think there is only the first option on the Internet, why my option may not be suitable?

Answer 1

Because the server, in addition to your token, also has APP_ID and CLIENT_SECRET which it uses to access the API. And even if someone can intercept your token, he will not be able to reach the API without these credits.