Lemma is a daily 6x6 Sudoku for iPhone and iPad: one puzzle a day, the same for everyone, free forever.
One paragraph
Lemma is a daily 6x6 Sudoku for iPhone and iPad. Everyone plays the same puzzle, called a lemma, on their own date. Players prove it in two to six minutes, see where they rank, and compare times with their people in private circles without ever spoiling a digit. Hints show their reasoning instead of the answer. The daily lemma is free forever, with no ads; Lemma Plus adds unlimited extra lemmas and the archive. Paper by day, chalkboard by night.
