Move and rotate your head to keep the line passing through the circle without touching the edges!
The line will start panning perpendicular to the circle, and increase in speed and difficulty as the player progresses. The circle will remain in the center of view for the player, and they will have to move it around to manipulate the line through as it zig-zags.
For added levels of difficulty, perhaps it would be fun if the entire screen rotated slow. So, the panning will begin in one direction, and the player will have to adapt as the screen rotates.