Qchain is an upcoming blockchain-powered digital marketing, advertising, and analytics platform. Our direct buy advertising application aims to facilitate open, flexible, and inviolable cost-per-conversion, cost-per-action (CPA), cost-per-click (CPC), and cost-per-impression (CPI) transactions between advertisers and publishers through the use of smart contracts. We will especially place emphasis on facilitating cost-per-conversion transactions, which are more resistant to ad fraud, since the increased temporal and financial costs of conversions relative to clicks filters for human interactions. Our other central application, the Qchain Personal Data Management and Marketplace (PDMM) application, will add everyday Internet users as a third participating agent to the traditional advertiser-publisher binary star system. Internet users will be able to monetize, control, and permissionize their data with the PDMM application, advertisers will be able to ethically obtain more detailed and up to date data that helps with targeting, and content publishers will financially benefit from the higher conversion rates that come with more relevant targeting. Thus, the PDMM application offers the advertising industry progress on the fronts of data privacy and data quality.