Collecting/avoiding games - they're all easy, right? After all, mousing over things is pretty simple. So this game tries to make it a leetle bit more difficult. Level 1 will lull you into a false sense of security, but keep on playing.
Use the blue thing to grab the green things, avoid the red things.
If you do manage to finish, enjoy the completion screen animation as a well-earned reward.

Oh, the context menu lets you turn sound off & stuff like that. Probably best to do that between levels.

I disclaim all responsibility for loss of sanity while playing this game.

Don't say it's too easy unless you can complete the hard difficulty.