Machine and deep learning techniques are increasingly applied in the tourist domain to understand past user behaviors, forecast future trends, and provide recommendations. Traceability and authenticity of data shared by users are essential to guarantee the quality of results obtained from their analysis. Blockchain is an emerging technology that is able to ensure such property by making information immutable and maintaining a set of metadata about its production and sharing. At the same time, a set of incentives could be implemented to promote the production of this kind of information to increase data availability and data quality. Smart contracts and decentralized applications could also be successfully applied for this purpose. This paper presents a complete solution based on the design of a set of smart contracts for traceability, immutability, and incentive implementation, together with a decentralized application for increasing the usability of the approach.