User Protocol Reference
User
Undocumented
setIdentifier(_:)
Sets the unique identifier for the user.
Setting a user ID ensures subsequent Merchant activity (such as installs or purchases) is attributed to a user. This can either be your user ID, email or a stable hash of one. You can use this later to look up orders, activity and identify the user in Webhooks. String with a maximum length of 255.
@note: You should set the user ID in your login handler.