Cages (Mind Loft)

Cages is the killer sudoku in Mind Loft's sudoku set. No digits are printed at the start. Instead the 81 squares are divided into dashed, coloured cages, each labelled with the sum of the digits inside it, and digits may not repeat within a cage. The usual sudoku rules still apply: every row, column and 3x3 box holds 1 through 9 exactly once.

Each puzzle has a single solution that can be reached by logic, without guessing. You can tap a square and then a digit, or pick a digit first and tap squares to fill them; Notes mode pencils in candidates, and on a desktop the arrow keys and number row work. Each number button counts how many of that digit are left to place. There is also Undo, Erase, Clear, an auto-move option, a Hint button and a timer you can show or hide. Wrong entries are not flagged, so catching your own mistakes is part of the solve, and a clean solve earns a perfect score.

A new grid arrives every day at midnight Eastern, and Sundays bring a harder edition with fewer, bigger cages. Past boards are kept in an archive with each day's standings. Mind Loft's sudoku set also includes Suds (classic), Quilt (jigsaw), Sando (sandwich), Sixes (6x6), Knight, Diag, Frame, Towers and others, all in the same layout.