Hi @devi, as far as I am aware there is not a Javascript API which will work with Tobii Dynavox range of eye trackers, however this forum is intended support with the Tobii EyeX and C4 Eye Tracker and associated SDK’s.
To be certain, I woudl advise you to get in touch with Tobii Dynavox Support department directly @ https://www.tobiidynavox.com/support-training/ for an answer to your query.