The invention generally relates to a tool for planning a communication campaign. The invention provides systems and methods for communicating through mobile devices in which a publisher can model the effectiveness of a customer's communication campaign as a function of media purchase quantity to aid the customer in selecting a purchase quantity that optimizes a ratio of return on investment to risk. The publisher can do this by providing the customer with access to a computer server system that includes a campaign management tool with an ROI simulator. In certain aspects, the invention provides a method of planning communication on mobile devices by receiving a set of communication campaign parameters, simulating effectiveness as a function of units purchased for the received parameters, and for providing the simulated effectiveness for a plurality of values for the units purchased.