I can't edit a boat someone shared with me

You can view a shared boat but can't change its settings or thresholds. That's by design — guests have read-only access.

Checklist

1. Guests are read-only. As a guest you can view all the boat's data and arm the anchor watch when aboard, but you can't edit configuration or alarm thresholds, run device setup, share the boat, or use backup/restore.
2. It's not a bug. These limits are intentional — ask the boat's owner to make any changes you need.
3. You can still arm the anchor alarm. When you're physically on the boat, guests are allowed to set and arm the anchor watch.