Idea Summary
We need some option to define application variables logic.

Use Case
We should be able to define some logic to find/define the values in application attributes or even application settings. Today this is always hardcoded and we must code in our CI/CD deployment scripts to find for this fixed values and update it before the installation of the application in the destination database. 

We know there's the option to create application items and define the logic there, however this didn't work to us, let's assume we want to define the logout URL, the cookie domain, the reset password URL, or even the table schema, every single property could be defined as a dinamic search, everything is today already parametrized in our tables in each environment, however Apex didn't know this at some situations, only after the session creation, which did not apply for all scenarios. 

Preferred Solution (Optional)
Extend the fields on application settings, application attributes, application substitution strings to define some logic to calculate this instead of hardcode it.