Reduction: turn the 4×4 into a 3×3

The 4×4 has no fixed centers, and every edge is split into two pieces. Reduction fixes exactly that: first you build the six centers, then you pair the twelve edges, and from there the cube behaves like a normal 3×3 that you solve with what you already know. Only two new cases show up at the end, the parities, which don't exist on a 3×3.

Press the CYCLE button (the small cube icon, next to the Aa letters) to swap the colors so they match your own cube.

i In the centers and edges phases you'll see some pieces of the cube in gray: that's on purpose. Gray is whatever doesn't matter yet, so you can focus only on the pieces of that case. Drag the cube with your finger to see it from behind. You can view the whole cube in color by pressing the button in the playback area.

↔ Drag to rotate the cube

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