After leaving Industrial Light and Magic, Glass worked on several projects with Marc Canter, founder of Macromind which later became Macromedia, birthplace of Shockwave and later Flash animation & multimedia software.
Glass later developed an application that allowed a user to enter an audio blog entry from a remote cell phone location. His small start-up, known as AudBlog, was eventually folded into a partnership with Evan Williams, of Blogger.com, and the duo then created Odeo, a podcasting company.
In 2006, while with Odeo, Glass helped to create and develop the seed idea for what would eventually become known as Twitter. Not only was Glass the prime motivating force leading to its eventual development, he is acknowledged as being responsible for coining the name "Twitter", which began as the abbreviated version, "Twttr," and was later changed to "Twitter." In the book, Hatching Twitter, by Nick Bilton, Glass is given credit as being a co-founder of Twitter, having helped realize the idea, and designing some of its core features.