Personal data, like demographics and preferences, as well as more specialized datasets, like consumer behavior patterns or market research findings, are among the kinds of data that can berummy r sold. The idea behind data-selling apps is that people have useful information that can help others. For example, a user's shopping habits or preferences may provide them with insights into consumer trends that a retail company could find extremely valuable. Users can use these applications to make money off of the experiences and interactions they have on a daily basis.