CSI-COP deliverable D2.1 is a public research report realised from the exhaustive literature review conducted for Task 2.1 by the involved partners in the research phase of the EU Horizon2020 science with and for society (SwafS) project Citizen scientists investigating cookies and app GDPR compliance (CSI-COP). With the report produced from the next T2.2 research task, deliverable D2.2 (due M06), D2.1 will lead to the development of CSI-COP project’s framework for best practices in inclusive citizen science recruitment and engagement. D2.1 focused on CSI-COP’s research questions: 1. Whether citizen scientists developed scientific skills and competences? 2. If participation acted as a motivator leading to informal and formal science education of young people and adults? 3. Whether participation countered perceived anti-intellectual attitudes in society? 4. Whether participation raised the scientific literacy of European citizens? 5. Whether participation promotes social inclusion and employability? 6. Best tools for citizen science reporting and interaction with researchers? 7. Best platform for managing citizen science’s data collection? 8. What are the existing types of platforms used by citizen scientists and their experiences with them? 9. Challenges in the management of collected data? 10. Online support - requirements and experiences of citizen scientists? Summary of findings are: A. Participation in citizen science projects provides further learning opportunities for inquiring minds, with the activities extending the learning experience. As an informal learning experience, citizen science is notable for involving many of the procedures of formal science, including gathering data, testing hypotheses, and modeling outcomes. Through engagement with professional scientists, citizen scientists gain valuable access to opportunity to learn and to generate new knowledge. B. Volunteers participate in citizen science projects for many reasons, such as a willingness and a desire to contribute to science, learn science, and for fun. Studies showed that volunteers' motivation to participate included a number of factors such as values, altruism and concern for others, understanding, social, career, ego protective, escape from negative feelings, ego enhancement, personal growth and self-esteem. CSI-COP referred to various sources of information: journal articles, webpages, official reports, books, book chapters, professional blogs, conference proceedings, doctoral theses, and other sources of reliable information. The vast majority of the sources are journal articles (just under 56%). Citizen science activity is well communicated through webpages and blogs (aggregate number of CSI- COP D2.1 source, 23.48%). Figure 1 illustrates a map of the spread of these sources. A massive concentration of citizen science activities exist in USA, Germany, UK, Australia and a few other countries. CSI-COP D2.1 full report of ‘citizen science best practices’, with detailed answers to the project’s research questions, please download from: 1. CSI-COP website ‘Project Results’ page here: https://csi-cop.eu/projects/ 2. Pure portal, Coventry University from here: https://pureportal.coventry.ac.uk/en/projects/cs- research-report-public-report-on-current-methods-in-cs-engagem