A system for providing product recommendations for two or more members of a group, including a wearable device comprising a reader for reading product information from a product and a user feedback interface for providing a product recommendation; and a computer unit integral with the wearable device or in data communication therewith for storing personalized data for each group member, for receiving a user selection of two or more group members, and for combining the personalized data for the selected members. The personalized data is personalized biological data or product recommendation data derived from personalized biological data. The system is arranged to read product information from a product using the reader and generate a product recommendation for the product, for the selected members, using the product information and the combined personalized data, and to cause the generated product recommendation to be provided to a wearer via the user feedback interface.