Shift 4 is now available to play and it brings with it a shiny new iPhone app of the original Shift experience to take with you on-the-go. If you're familiar with the Shift series so far, a lot of the elements in this game will seem very familiar. However, twists do come, as you will eventually find yourself having to control more than one silhouetted fellow. You've now got to use a team of folks to reach the exits and advance.

If you've played the original, or the even better update to that one, then you probably will be thrilled to know that Tony has just released a third game in this fantastic series that takes the concept of negative space and turns it upside-down. Shift 3 extends the familiar jump and run, puzzle-platformer formula by adding a few surprises.

The original Shift was an interesting platform game that used negative space as an entertaining hook, but it came with a few problems that ultimately made it feel unfinished and experimental. Now, Tony of Armor Games has released Shift 2, which is basically the game the first one should have been. It's not enough of a leap forward to warrant the "2" in its name, really, but it refines and expands upon the original concepts to deliver a smoother, more drinkable dose of run/jump/puzzle distraction.

Shift embraces the same negative-space-centric platforming concept as Yin Yang, but in a style more elegant, more minimalist, and more pulsating with sexy-sweet spy music. With a press of the Shift key, you are flipped beneath the floor on which you are standing, and reverses both your body color and gravity. It's a unique platformer with a twist, and it's a good deal of fun.

Yin Yang is the latest platform game from Nitrome studios, in which twin gods team up across two parallel universes. Nitrome again delivers an interesting exploration of a concept, a platformer about metaphysical duality, and it offers a healthy plate of puzzle-levels to allow you to absorb all the flavors.