Some thoughts!
I love how smooth the movement's animation is and the snake's silly eyes looking for the apple.
The sound of the apple's bite plays some milliseconds later for me. It doesn't happen at the exact moment the snake closes its mouth.
I felt comfortable playing even with the field and snake being the same color. You could implement a color picker function for the snake and background. Also, have the chance to select one of some other fruits or even randomize them.
If you die with a long snake, it takes forever to do all the explosions! My mother thought my fan went down. After the fifth one, you could lower the explosion's volume and call the high score screen.
That is it! I liked it a lot! :)