Educators around the world have employed different technology-based learning tools to smooth the studying experience of learners in various fields. English teaching is no exception because English is an international communication tool that is used in many countries and communities. English speaking is considered to be one of the most challenging skills that requires mastery to be fluent in English. Numerous studies have examined the advantages and drawbacks of using technology to teach English-speaking skills. However, the number of studies focusing on the ChatterKid app is limited. Based on the mentioned facts, this study was implemented to evaluate the influence of using the ChatterKid app on students’ speaking skills at Thai Nguyen University of Education in Vietnam. Ninety first-year students participated in this quasi-experimental study for 12 weeks. The tests and questionnaire were applied to collect data; SPSS analyzed the data to draw the conclusion for the study. The findings indicated that the ChatterKid app significantly improved the speaking level of students, especially fluency, and students had positive attitudes towards the use of this app.