Nine puzzle and board games. No accounts, no sign up, no timers pushing you along.
627 puzzles, every one generated and then verified by computer to have exactly one solution. No guessing, no dead ends, no puzzle that turns out to be impossible halfway through.
The four board games can be played with the person next to you on their own phone. Chalk finds the other phone over the local network, or sends the moves as a short chirp through the speaker, which works between any two phones with no account, no pairing code and no connection of any kind. Or pass one phone between you, or play Chalk itself at one of three levels.
There is no account and nothing to sign up for. Your progress, best times and settings are written to a file on your own device and never sent anywhere. Every puzzle ships inside the app, so the games work in a tunnel, on a plane, or with the wifi off.