Do I need to make an app to oauth for admin access?

I have an app that I want to allow users to integrate their Shopify stores with to make api calls to. Do I need an app for this? The app doesn’t integrate within the store at all, just need to communicate with the admin api.

Example flow:

User logs into MyApp → clicks “Integrate Shopify” button → Follow Shopify OAuth steps for valid admin token → Make calls from app to User Shopify admin from MyApp Server.