The app will analyze the current season and climate to decided which subjects of Chinese painting would be used as the background-image. On the other hand，users can choose which subjects of work they like too. The color of the sky has a interesting interaction with the painting and with the subject of painting. I hope that this app can let more people worry about the nowadays environmental pollution. In addition, may be it can attract some Chinese young people to know more about the Traditional Chinese Art. Since there are too many young people who know nothing about their own country's culture.