The publication sources are influential SSCI-indexed or Scopus-indexed journals and to some extent show the characteristics of the combination of modern technology and language learning. Researchers of the studies reviewed used a variety of digital learning environments, not only including the widely used Kahoot (Hung, 2017 Zou, 2020 Alawadhi and Abu-Ayyash, 2021 Almusharraf, 2021 Chen, 2021 Ebadi et al., 2021), Duolingo (Bahjet Essa Ahmed, 2016 Guaqueta and Castro-Garces, 2018 Ajisoko, 2020), Moodle (Barcomb and Cardoso, 2020 Ho, 2020 Qiao et al., 2022), and some gamified English learning APPs used in China like Baicizhan (Dindar et al., 2021) and Shanbay (Fan and Wang, 2020) but also self-designed gamified software or webpage (Hwang et al., 2017 Hung, 2018), which indicates that digital gamified tools could play a vital role in EFL/ESL instruction and learning.

Based on Supplementary Table 1, most of these journal articles were published in the last 6 years, which indicates that gamified EFL/ESL instruction is a relatively new field of research.

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