What are the differences between the original Hexcells, Pro, and Infinite?

What are the differences between the original Hexcells and its sequels, Hexcells Pro and Hexcells Infinite?

1 Answer

Forums report that the puzzles in the later editions are progressively harder than their predecessors.

Hexcells Plus (Feb 2014) adds 36 puzzles.

Hexcells Infinite (Sept 2014) adds 36 puzzles, a random puzzle generator (each puzzle has a number and can be shared), mid-level saves, cross-platform cloud saves, and the ability to load custom user-made levels.