The Listalux privacy policy is simple: we do not collect any data from you through the Listalux iOS app.
Data synchronisation, sharing and collaboration functionality provided in the Listalux app is built upon the CloudKit framework provided by Apple. Your data is stored in a database associated with your own iCloud account, as is not accessible by us. If you share a shopping list with another iCloud user, they will have access to any data you have entered into the shared shopping list. If you have granted permission for “User Discoverability” on the initial launch of the app, the iCloud user(s) you have shared the list with may also be able to see your name.