Aliases are created automatically, based on the location of the user. You can always replace it with a custom property uploaded by you. Click here to read more about it.
It’s always better to send the event properties right after the authentication/registration process that the application has. However, you should also be sending the user ID to UXCam at different points of the user journey, other than the registration. If you send the user ID again at a later time point we will be able to map back all the previous sessions of this device to the respective users, so its always recommended to send this a different points of the user journey.
Updated about 2 years ago