A system includes at least one hardware processor and a memory storing instructions which, when executed, cause the hardware processor to perform operations including identifying a notification trigger configured by a user of a target computing device, the notification trigger including at least one trigger condition and notification content, the trigger condition references a value from a trigger data source and includes a condition based on the value, the notification content includes content provided by the user, receiving the value from the trigger data source, determining, based on the value, that the at least one trigger condition is satisfied, and presenting the notification content to the user on a target computing device associated with the user, the notification content is presented in a target content venue configured to present third-party advertisements to the user.