1) The document discusses the rise of mobile social commerce and how 50% of Groupon's business is expected to come from mobile in the next two years. It also outlines trends in mobile e-commerce sales.
2) Various mobile social commerce applications are described, including social integration, check-ins, reviews, group buying, and style/shopping feedback apps.
3) A case study discusses how American Express enables social offers for merchants through deals on Facebook and Foursquare.