There is a bug with on-screen buttons (if you click on them with mouse or touch on the phone/tablet):
1) If you press any button while not on the world map, you'll move one step west/north.
2) If you try to leave the world map, you'll make an extra step west/north (or try to make -- if there is no space west/north, you will be softlocked and need to restart the game).
3) The hint button doesn't work.
4) If you enter the world map, the locked area will not be grayed out.
Tested on the web version 1.1.0 on Android (Firefox, Chrome, Mitch) and Windows (Firefox, Edge)
Despite this, I was still able to reach the lava island, and I quite enjoyed the game. Keep it up!