The mobile Web is significantly changing the world. More and more people are replacing their PCs with various mobile devices for both work and entertainment. This change in consumer behavior is affecting the cybercriminal underground economy, causing a so-called “mobile underground” to emerge. This presentation provides a brief overview of some basic underground activities in the mobile space in China. It describes some of the available mobile underground products and services with their respective prices, including Premium Service Numbers, SMS Forwarders, SMS Spamming Services and Devices, iMessage Spamming Services and Software, Phone-Number-Scanning Services, and App-Rank-Boosting Services.