Shanghai Hosts Its First Maker Carnival

First time accepted submitter spanner888 writes "The first Shanghai Maker Carnival was held this weekend in conjunction with a Creation Exhibition, an arts and crafts expo with about 200 exhibitors. Makers attended from Shanghai, Beijing and Shenzhen and visitors came from around China. More photos are in this post, and videos in this one. Other photos can be found in this thread." I like the video that appears to show a smartphone's camera being used as the basis of an input device for a laptop; can anyone out there better explain it?