Mobile gadgets, mobile teaching, and mobile learning aids have quickly risen to prominence in the industrial revolution 4.0. Mobile devices' intelligent features enable teaching and learning anywhere and at any time under wireless networks. Mobile-assisted language learning (MALL) is therefore anticipated to improve learners' English proficiency. However, before mobile teaching and learning applications are developed, the teachers' capacity to use wireless mobile technology should be verified. The present paper examines how EFL instructors in Ho Chi Minh City, Vietnam used mobile devices to instruct English. Quantitatively, 45 EFL teachers participated in the study and responded within 15 minutes to a questionnaire containing 12 statements. Three open-ended interview questions were given to seven teeachers, and the data was obtained through a qualitative one. The findings show that EFL teachers are self-assured in their ability to employ mobile technology and adjust to the unpredictable changes of modern high-tech portables to aid in their English teaching.