For example, we have two environments: CI - Staging and want to add some customizations for each environment. Here I will try to customize server URL, app name.
First, we create two targets for 2 environments by duplicating the main target:
For each target, we will define a custom macro. Here I will define macro named "CI" in build settings of target CI, macro named "STAGING" for target Staging.
We will create a header file to define SERVER URL as below:
If you want to do more customize, for example: Change app name for each target:
As you can see, value of SERVER_URL and app name is changed for each target :)