Ionic3 - ios - Access-Control-Allow-Origin error

We are building an application based on a simple login,registration function in the beginning of the app.
We’ve changed the server protocol to https from http because of social media restrictions and requirements.
Now the server not allows the app the communicate with it, the only option that was successful is to set the whole apache servers header to enable calls from all origins, wich is a huge security risk.

Can anybody help me, us with a workaround, solution or anything?

Thank you very much!
Daniel