Chalkline: Deduction Puzzles

A murder has been committed. Everyone in the building was standing somewhere when it happened — and exactly one of them was alone with the victim.

Chalkline gives you a floor plan, eight suspects and a handful of statements. Work out where every single person stood, and the killer reveals themselves.

HOW IT WORKS

Each suspect tells you one true thing. "He was next to a TV." "She was alone with Carla." "He was exactly two rows north of Ivo." Cross-reference the statements, place everyone on the map, and only one arrangement can possibly be true.

Then apply the one rule that matters: the victim was alone with exactly one person. That person did it.

NO GUESSING, EVER

Every case is checked by a solver that only makes moves a person could make on paper. If a case is in the app, it can be reasoned out from start to finish — no trial and error, no lucky guesses, no dead ends. Difficulty is measured by how much deduction a case genuinely takes, not by how many clues we deleted.

WHAT YOU GET

• 60 cases in the archive — 20 easy, 30 medium, 10 hard
• A brand new case every single day
• 12 locations: a mansion, a hotel, a yacht, a museum, a cinema, an office, a gym, a campsite, a bowling alley, a car dealership, a burger joint and an electronics store
• Hints that teach instead of spoiling: they tell you which suspect to work out next and whose note holds the answer, so you still make the deduction yourself
• A streak for solving the daily case
• Finished cases stay in your files, and you can replay any of them
• Complete in English and German
• Plays entirely offline — no account, no sign-up, no connection needed

FOR PEOPLE WHO LIKE

Logic grid puzzles, nonograms, sudoku, cryptic crosswords, locked-room mysteries, and any puzzle where the answer is provable rather than plausible.

Chalkline is free to play. One optional purchase removes ads forever.

Recent changes:
1.2.0: no case left behind.
Leave a case halfway and your board, clock and hints are waiting when you return. Case files now start easy and grow harder, every case has its own title, and new daily cases lean on fewer "north of" clues. Plays with TalkBack, fits tablets in landscape, and clearer clue wording in English and German.