The Good: I really like the presentation, the title cards to each level, the intro at the beginning and the ending are all really nice. The puzzle design is clear and well done, and the level art clearly telegraphs hazards and goals. I liked the implementation of the gravity change with a teleport gun and the camera transitions are smooth and unobtrusive. Audio fit well and was well implemented.
The Bad: That jump.
I'd like to see that jump get some air control and coyote time (the typical platformer jump) and I think you could easily expand upon this with more levels with just the few mechanics you have so far. I felt like I could understand how to get to the goal but my legs just wouldn't move where I wanted them to.