One of the major issues in online teaching is the lack of practice during speaking lessons. This mainly results from the lack of microphones, slow Internet connection, shyness or pure laziness. The study focuses on the use of Flipgrid to create an English-speaking environment for students. The research was conducted with 70 first-year students at University of Engineering and Technology, Vietnam National University, Hanoi during four weeks. They were asked to post their own audio files or videos on the Flipgrid groups, and then read the automatically generated captions to check their pronunciation. The lecturer also listened to the files and gave them feedback. The data were collected through students' interviews and the analysis of their Flipgrid posts. The findings show that Flipgrid improves learners' fluency and pronunciation, as well as helps them become more confident when speaking English. The study suggests that Flipgrid can be used as a tool to practice English speaking skill online.