Pretty fun! Does seem to have some glitching issues on my iPad Pro - particularly if I cross through a race flag the sound completely glitches and the frame rate stutters for a second.

EDIT: one further note, once the skier has achieved a certain speed, and it shows the flames underneath the skis, it's almost like the graphics are being rendered in separate loops. The skier maintains a consistent frame rate, but the trees seem to be rendered almost at a half frame rate, so they appear to be slightly flickery. I can't tell if this was done deliberately for optimization purposes but it was a bit distracting.

Theres a couple things that cause stuttering: the first time a sound is played it is decoded, and the first time a particle effect is seen its shader is compiled (snow and flame particles).

The bug your describing with the trees I think is just a by product of my having not implemented proper 'pixel perfect' camera positioning, ie: the trees are being rendered off center from a pixel so they look glitchy, while the character is always at the same position on the screen so doesnt look glitchy.

I'm suprised your ipad pro has the above sound/shader issue as noticably... Shader compilation is also pretty brutal on windows.

Thanks for the feedback and bug reports.