a system for targeting advertising can include a communications interface and a processor . the communications interface can receive data associated with times of use of applications . the processor can be communicatively coupled to the communications interface and can categorize the applications by genres . the categorization is within a time of use group and is based on at least part of the retrieved data . the processor can also determine priority values associated with the genres based on levels of use of the applications during a period of time associated with the time of use group . the processor can also identify a current time and determine an advertisement according to at least one genre of the genres . the at least one genre can be associated with a highest priority value of the determined priority values . the period associated with the time of use group can correspond to the identified current time .