1. One or more computer-readable storage media storing computer-executable instructions that, when executed by one or more processors, instruct a computing device to perform acts comprising: receiving an identifier of a user from a mobile device; identifying items of interest to the user based at least in part on the identifier; determining a geolocation of the mobile device; identifying a merchant within a predetermined proximity of the geolocation of the mobile device; comparing the items of interest to the user with items offered by the identified merchant to determine whether the merchant offers an item of interest to the user or an item related to the items of interest to the user; and when the comparing determines that the merchant offers the item of interest to the user, generating a notification of the determination.