His work is at the intersection of human-computer interaction, human computation, and artificial intelligence, with a focus on developing innovative technology that serves people with disabilities in their everyday lives. He's worked on the cloud-based screen reader WebAnywhere, which led him to Raising the Floor Consortium and the architecture committee for the Global Public Inclusive Infrastructure. He's also the creator of VizWiz, an iPhone application that lets blind users take a picture, speak a question, and receive answers from the crowd quickly (usually in less than 30 seconds). Most recently he's been working on "closed-loop crowd control and support" that allow dynamic groups to act like highly-skilled individuals.