The app I want to develop is mostly running in the background, so there will be no heavy graphics or computations.
I do not have a high budget, which is why I would prefer to buy a (used) Mac with the minimum required specifications that is able to run the latest version of Xcode and iPhone simulator. I need to buy a Mac to run Xcode for iOS app development. I'm planing to develop an app with React Native for Android and iOS.