Methods and systems for sending marketing messages to mobile-device users from a mobile-commerce platform are described. In various illustrative embodiments, a marketing message is transmitted to a mobile-device user before, during, or after a transaction between the mobile-device user's mobile device and the mobile-commerce platform. The marketing message can be generated and timed based on rules input to the mobile-commerce platform by a merchant and can be based on historical transaction data associated with the mobile-device user, transaction parameters associated with a current or a most-recently-completed transaction involving the mobile-device user, a transaction type of a current or a most-recently-completed transaction involving the mobile-device user, or a combination thereof, depending on the particular embodiment.