Unique twist on an old classic. Is does take a long time to get to a size where you need to start avoiding yourself. Maybe something to make it go faster (more things to potentially eat than just one) would help? I like the night/day effect, though the object I thought was a star is probably a moon, and actual stars would be nice, especially if you saw more stars the bigger you got. As others have mentioned music and SFX would help.

I like that on land you had houses to eat and on water you had boats. Maybe a little more variety of objects would be good. Having little people to eat that fled from you early on and increased your size by a tiny amount would make the initial start of the game less tedious?

Still a solid entry!

3d snake on a planet. This is a unique game idea. At least I never saw it before. 

In the beginning the game is very slow and boring. You could add some obstacles to avoid or meteors maybe?

Also sound and music is missing which is a bit sad.