The DL version is great with mouse, but the browser version is VERY great on a tablet. First game that isn't OSU that goes this well on a tablet, I'd say. I imagine you didn't design it with that in mind, but perhaps that is a niche you could try to pursue if you were to take the project further.
The gameplay and boss design have an idiosyncrasy that I'd like to know your philosophy behind, though. 1)Spin the mouse around to attack 2) while spending stamina to continue spinning 3) against a moving boss. 1 can't be removed, but I think without 2 or 3 the experience would be more fun. Having limited stamina against bosses that move this much on an attack system that gets a while to get going gives a feeling me a feeling of being on a leash. The damage output isn't that absurd to need a limiter, and the boss isn't that static to get them on an infinite that melts their HP instantly. I'd even argue the real stamina bar is out-universe, in that it's how long the player can spin the mouse (perhaps an interesting approach to engage with this would be that the longer you spin, more mouse spinning is necessary to perform a spin in-game, so the player themselves can feel theyre out of stamina as they spin, rather than the game telling you so after a while. the different weapons then would have different timers or growth rates to when they start becoming harder to spin?). Or, if stamina is really necessary, bosses could have stronger attacks to keep the player dodging, but move less, to not have your mind split between survival, pursuing and mouse spinning.
Lastly, and this is less professional and more personal, the worm boss shouldn't come so soon, this battle isn't very interesting or as fun as the others, and you're so little upgraded for it too... (And to not leave it as a plain complaint, a concept: the worm coils around the stage and attacks by constricting; some of its segments are walkable/rollable and you have to escape through them while attacking to survive the battle.)
Overall, fun game with a lot of room to become a full game