Mobile phones are a tool that the majority of students have and can use so they can be very useful as a tool for learning. If a students does not have a mobile phone, then they can always work with another student. If lectures were more engaging and student focused then students would be less likely to be looking at their mobile phones. Also, it is not only students who are addicted to phones but teachers also often look at their phones when teaching. I have only really encouraged them to be used as dictionaries and for research purposes.
I would be interested to know about any mobile apps (apart from Kahoot) that might work well in an EAP setting. I have come across the ELSA app which helps with pronunciation. The drawback is it is not free and it would seem better suited to self study. There is also the Cambridge IELTS app (and many more) that can be helpful for students.
I find that when teaching online, students often use their phones to join the session. This may be because the link doesn’t work on their laptop or they may be out and about. Students seem to think that with an online course they do not need to be in a room on their own. Background noise can be very distracting and it can prevent them from participating in breakout room activities. But I suppose as a last resort it is better to join the session by whatever means possible.