Timothy App received a BFA from Kent State University and an MFA from Tyler School of Art. He taught painting and drawing at MICA from 1990 at both undergraduate and graduate levels. In 2008 he became Interim Director of the Hoffberger School and served in that capacity through Spring of 2010. 

From 1968, App had 20 one-person and 5 two-person exhibitions, as well as over 200 group shows, exhibiting regionally, nationally and abroad. In 1988, his work was the focus of a 20-year survey exhibition at American University's Katzen Art Center in Washington, DC. During his time at MICA, App twice received the Trustee's Award for Excellence in Teaching.