Hi, i am developing an android application where user’s can sign up for an account through the android application. i was thinking is it possible to create the user dynamically through the sync function?
It is not possible to create user docs through the sync function.
If you are not using one of the third party auth implementations (e.g. facebook, openID Connect), then you will have to implement a custom auth flow and create user docs via the ADMIN REST API.
Take a look at the authentication section of the docs for descriptions of the different auth flows.