Ivonne Jansen presented on apps challenges and their impact. Some key points: - Apps challenges can produce many apps but require significant effort and cost to run. It is debated whether the value created is worth the cost. - Challenges aim to create both economic and social value, engaging citizens, developers, and governments. However, both challenges and open data come with risks around privacy, data quality, and infrastructure that must be addressed. - When done well, challenges can spur innovation, new combinations of data, and increased engagement and involvement of citizens with their government.