How can multiple wearable devices be linked to the same user?

That is an excellent question. Terra allows you to provide a reference_id parameter when creating an authentication url or a widget session which will be assigned to the user (device) and sent with every payload. You can pass in the user-id you use within your system to connect all these Terra users together.

You can also use the reference_id when hitting the /userInfo endpoint to list all the Terra users that are linked to that reference_id

Thanks. I already have a few users/devices that don't have reference-ids assigned. Should I deauthenticate the users and reconnect them or can we migrate the devices to new terra users

There is no need for that. You can reassign the reference_id of the user by going to the dashboard and navigating to Tools > Debug > Users and clicking the arrow on the arrow on the right - opening up the details pane where you can edit the reference id.

Thanks, that helps alotYour welcome :)