Parallelus is a game all about having individual control over your left and right hands. The player is forced to distinguish between what the two different sides are doing as they doge bombs and collect hearts. With a thumb on the left and a thumb on the right, bombs and hearts fall from the top of the screen to the bottom. With each move the player will move their slider toward the pieces. This game is an excellent way to see just how your mind handles varying patterns and will sometimes be very enlightening for those who think they have excellent coordination.
If things start getting too crazy and the players fingers accidentally slide off the screen, the game will pause and wait for them to set their fingers back. This is a nice feature because the game will stretch what you can do and will have your thumbs flying all over the place most of the time off the screen if you're not careful. This game will offer some entertainment up front, keeping the player struggling to concentrate on two different movements at the same time. But overall, this game will leave players bored after a few intense rounds.
Parallelus is one of those games that is great up front but the replay value goes down drastically as you progress. I'd recommend passing unless you are the type of player who enjoys constantly doing something over and over to get a better and better score. There is just not enough variety in gameplay.