Onboard a developer for a Zoho Creator application from Zoho One

Onboard a developer for a Zoho Creator application from Zoho One

Hello, 

Could someone tell me how to add an external developer to a Zoho Creator application from Zoho One?
It's not very clear and I can't find any real explanation on how to proceed.

This developer also has a Zoho One account and would like to add one of our applications to his workspace in his Zoho Creator account.

Does this add her as a paying user to our Zoho One account?

Thank you,
Charles