On Ugly Betty, Blue starred as Cliff St. Paul, a photographer at Mode magazine and love interest to Wilhelmina Slater's faithful assistant, Marc St. James, played by Michael Urie.

Before his breakthrough role on Ugly Betty, David made guest appearances on Veronica Mars, FX's series Dirt, and Disney's comedy The Suite Life of Zack & Cody.

One of Blue's feature film appearances was in The Comebacks, a comedy spoof on inspirational sports movies starring David Koechner, Matthew Lawrence, and Bradley Cooper.

The musical was re-imagined by Howard's partners Marsha Malamet and Dennis Green and performed one night only at Los Angeles' Hayworth Theatre as part of the Bruno Kirby celebrity reading series, directed by his Ugly Betty co-star Michael Urie.

David had a podcast channel called Out of the Blue where he interviews famous actors such as Torri Higginson, Claudia Black, Robert Picardo and Chase Masterson can be accessed on his Patreon page.