This exploratory study reports the factors that led to post-use changes in authorial confidence for students who used a newly-developed authorial voice learning technology. The AVATAR prototype is a student-facing academic writing learning technology designed to help first-year university students become aware of and reflect on their authorial voice in English argumentative essays. 23 first-year Fijian university students who used English as a Second language (ESL) trialed AVATAR using an authentic argumentative essay assignment. Pre- and post-use authorial confidence data was captured via questionnaires and interviews. Key findings showed a statistically significant difference between preand post-use authorial confidence. Deductive thematic analyses of interview responses AVATAR’s affordances for visualizing authorial voice in the participants’ written texts and a cycle of self-reflection on and editing for authorial voice. The findings have implications for authorial voice pedagogical support and the design and development of academic writing technologies.