This study investigates the acquisition of the L2 French vowel /y/ in a mobile-assisted learning environment, via the use of automatic speech recognition (ASR). Particularly, it addresses the question of whether ASR-based pronunciation instruction using a mobile device can improve the production and perception of French /y/. Forty-two elementary French students participated in an experimental study in which they were assigned to one of three groups: (1) the ASR Group, which used an ASR application on their mobile devices to complete weekly pronunciation activities, with immediate written visual (textual) feedback provided by the software and no human interaction; (2) the Non-ASR Group, which completed the same weekly pronunciation activities in individual weekly sessions but with a teacher who provided immediate oral feedback using recasts and repetitions; and finally, (3) the Control Group, which participated in weekly individual meetings 'to practice their conversation skills' with a teacher who provided no pronunciation feedback. The study followed a pretest/posttest design. According to the results of the dependent samples t-tests, only the ASR group improved significantly from pretest to posttest (p < 0.001), and none of the groups improved in perception. The overall success of the ASR group on the production measures suggests that this type of learning environment is propitious for the development of segmental features such as /y/ in L2 French.