If you like Sudoku, then you'll love Futoshiki. Futoshiki is another popular Japanese numeric puzzle game.
On a 5x5 grid the aim is to put, in each row and column, numbers from one to five, so they do not repeat themselves. Numbers must also respect the relational signs placed between some cells. Some cells may already be filled from the beginning. They are, like the relation signs, part of the puzzle and cannot be overwritten.
To make notes, simply tap the selected cell second time. Tapping once again exits notes mode.
For solving puzzles you get "win points". You can unlock new background themes with them.
The game includes a generator offering the player three difficulty levels, from easy through medium to hard. For each generated puzzle only one unique solution is guaranteed.