This chapter characterizes how interacting with data visualization using mobile devices, specifically a phone or tablet, differs from analogous experiences using a PC. It presents an overview of the topic according to three interaction modalities: touch, spatial gesture, and voice. The final section of the chapter considers opportunities for future research and innovation with respect to interacting with visualization on mobile devices, including prospects for multimodal interaction and multi-device interaction, as well as possible applications of recently proposed techniques in the field of mobile human-computer interaction.