Yes, 100%. Cube-Kala is and always will be free. No premium tiers, no paywalls, no ads. It's built by the community, for the community.

A standard Rubik's cube uses colored stickers to distinguish pieces, while all pieces on a Mirror Cube are the same color (usually silver or gold). Instead of color, each piece has a unique shape and size. As you scramble it, the puzzle physically shape-shifts. However, the internal mechanism is identical to a 3x3, so all standard solving algorithms (like CFOP) still apply—you just match shapes instead of colors.

The solver runs entirely in your browser using an optimized JavaScript port of Herbert Kociemba's Two-Phase Algorithm. Phase 1 reduces the cube state to a subgroup where corners are oriented and edges are in correct slices. Phase 2 then finds the shortest path to the solved state. By utilizing pre-computed prune tables and Web Workers (when available), it can search millions of states per second to find a near-optimal solution (typically 20-22 moves) without relying on a backend server.

Yes! Cube-Kala is built as a Progressive Web App (PWA) with extensive static generation and client-side logic. The 3D rendering (React Three Fiber), the solving engine (Kociemba algorithm), and the Playground timer all run locally in your browser. You only need an internet connection for community features like the World Map, Feedback, and the Community Feed.

The timer follows WCA (World Cube Association) standards. When you activate it, a 15-second inspection countdown begins. You can press the spacebar (or tap the timer on mobile) to start the actual solve timer before the 15 seconds run out. It records times down to the millisecond and stores your Personal Best (PB) locally on your device.

The reverse-move (or rewind) feature is designed for learning and debugging algorithms. If you make a mistake while executing a complex OLL or PLL algorithm, you can step backward exactly through your move history instead of having to reset the entire cube. This is especially helpful on the Mirror Cube where losing your place can result in a confusing, shape-shifted mess.