Methods and apparatus to enable a distinction between “new” and “used” digital content and to enable a market in used digital content files between mobile phone terminals and an electronic store, securely, by means of a wireless telephony network and a server complex to handle contents right management, transaction reporting, inventory, content delivery, payment, and billing. A server receives a signal generated by a wireless user device that was sent over a wireless telephony network. The signal indicates an election for returning at least one previously purchased digital content item. The server deletes user rights for the at least one digital content item identified by the received signal and sends information to the user device that generated the signal. Access to the associated digital content item at the user device is removed according to the sent information.