A system generates and displays to a user of a digital magazine a list of candidate topics. The system first receives a package name list from a user device of the user, and the package name list indicates computer applications installed on the user device. The system retrieves a package name-topic matrix generated based on information associated with a set of existing users of the system. The system compares package names included in the received package name list and package names included in the package name-topic matrix, and identifies known topics in the package name-topic matrix based on the comparison. The system generates a list of candidate topics for the user based on the identified known topics, and provides the list for display to the user. In response to candidate topics selected by the user, the system provides to the user content relevant to the selected candidate topics.