OCTO is a highly addictive logic puzzle, enjoyed by puzzle enthusiasts the world over.   

The rules are simple: numbers cannot repeat in octagons, rows, columns and diagonals, and they have to add up to the provided diamond and diagonal sums. Puzzle difficulties range from youngster-friendly to brutally challenging, as you master dozens of techniques that combine position logic and good old-fashioned math.  

OCTO puzzle books have sold thousands of copies, the puzzle has appeared in dozens of university newspapers and the OCTO has been featured in local and international puzzle competitions. If you are ready for a new logic puzzle challenge, then OCTO is for you.

App Features:

- 160 starter puzzles, including all difficulty levels
- Extensive instructions, including tips and solving techniques
- Work any number of puzzles at the same time! Your progress will be stored for each puzzle and will be available whenever you want to continue
- Replay feature allows sharing and "competitive puzzling"
- Check puzzle and Undo/Redo features
- Notes feature allows you to "pencil in" possible solutions
- Choose from a collection of artistic puzzle board designs