Orbs

Grab the ring and move it around with your mouse. Touch orbs of the same color to collect them and gain points.

Might seem dull or too easy at first but then things get more interesting as new colors appear. Use the A and D keys to switch your ring’s color and then you must only touch matching orbs. If you touch the wrong ones, you get penalized.

The words “slow” and “fast” also can appear, affecting your ring’s movement speed.

A clever game mechanic that could do well on mobile.