Code Duo — Deduction Duel
Puzzle
A two-phone deduction duel where the secret code travels by QR code
- Downloads
- 10+
- on Google Play
- Price
- Free
- No in-app purchases
- Updated
- Sep 4
- 2026 · v1.0.5
Screenshots
About Code Duo — Deduction Duel
Two players, two phones, one secret code to crack.
Code Duo is a face-to-face deduction game. The first player builds a row of colored pegs; the app turns it into a QR code. The second player scans it with their own phone, then works out the combination one guess at a time. Each player keeps their own screen, so the one guessing never sees the code.
Why you will enjoy it:
• A real in-person duo, each on their own device, with no peeking at the other screen.
• The secret combination travels by QR code, with no connection and no server.
• Clear feedback on every guess: a black marker for a color in the right place, a white marker for a right color in the wrong place.
• A game you can tune to your level: code length, number of colors, duplicates, and number of attempts.
• A solo mode to practice against a randomly drawn combination.
How a round works:
The first player picks their pegs and confirms a secret combination. The app shows a QR code. The second player scans it; the combination stays on their phone. They then make guesses: after each attempt, the feedback tells them how many colors sit in the right place and how many are present but misplaced. They refine their deduction until they rebuild the code, or run out of attempts.
Features:
• Two-player local deduction game built around a secret color code.
• Secret code shared by QR code, scanned from one phone to the other.
• Solo mode against a random combination.
• Game settings: code length, 6 to 8 colors, duplicates on or off, number of attempts.
• Color-blind mode: every color also carries a symbol so it stays readable.
• Interface in English, French, German, Spanish, Portuguese, Polish, Indonesian, Italian, Dutch, Turkish and Vietnamese.
• Statistics to follow your games.
Code Duo runs fully offline, with no account and no connection: nothing interrupts a round. Everything stays on your phones.
Put two phones on the table, build a code, pass the QR, and may the sharper deduction win.
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COUNTS — title: 23/30 · short: 67/80 · full: 1906/4000
Code Duo is a face-to-face deduction game. The first player builds a row of colored pegs; the app turns it into a QR code. The second player scans it with their own phone, then works out the combination one guess at a time. Each player keeps their own screen, so the one guessing never sees the code.
Why you will enjoy it:
• A real in-person duo, each on their own device, with no peeking at the other screen.
• The secret combination travels by QR code, with no connection and no server.
• Clear feedback on every guess: a black marker for a color in the right place, a white marker for a right color in the wrong place.
• A game you can tune to your level: code length, number of colors, duplicates, and number of attempts.
• A solo mode to practice against a randomly drawn combination.
How a round works:
The first player picks their pegs and confirms a secret combination. The app shows a QR code. The second player scans it; the combination stays on their phone. They then make guesses: after each attempt, the feedback tells them how many colors sit in the right place and how many are present but misplaced. They refine their deduction until they rebuild the code, or run out of attempts.
Features:
• Two-player local deduction game built around a secret color code.
• Secret code shared by QR code, scanned from one phone to the other.
• Solo mode against a random combination.
• Game settings: code length, 6 to 8 colors, duplicates on or off, number of attempts.
• Color-blind mode: every color also carries a symbol so it stays readable.
• Interface in English, French, German, Spanish, Portuguese, Polish, Indonesian, Italian, Dutch, Turkish and Vietnamese.
• Statistics to follow your games.
Code Duo runs fully offline, with no account and no connection: nothing interrupts a round. Everything stays on your phones.
Put two phones on the table, build a code, pass the QR, and may the sharper deduction win.
---
COUNTS — title: 23/30 · short: 67/80 · full: 1906/4000
What’s new
Version 1.0.5 · Updated September 4, 2026
The board no longer fills in while you build your guess: the row stays empty, then your pawns fly up into it when you submit, and the clues appear as they land.
Alternatives to Code Duo — Deduction Duel
Looking for apps like Code Duo — Deduction Duel? Here are 6 similar Android apps on Google Play. The highest rated is Kids Games (4 in 1) (4.6/5), and 4 of the 6 are free to download.
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| App | Rating | Price | Installs | Last updated | Compare |
|---|---|---|---|---|---|
| Code Duo — Deduction Duel | – | Free | 10+ | Sep 4, 2026 | |
| Colors Match Wear | – | 1 USD | 0+ | Feb 26, 2026 | Compare |
| Miyaelf Marble Shoot2 | 4.3 / 5 | Free | 10,000+ | Sep 12, 2026 | Compare |
| Kids Games (4 in 1) | 4.6 / 5 | Free | 500,000+ | May 20, 2026 | Compare |
| Our Bingo - Video Bingo | 4.3 / 5 | Free | 100,000+ | Apr 3, 2019 | Compare |
| Crown Breaker: Watch Arcade | – | 0.99 USD | 100+ | May 5, 2026 | Compare |
| Learn English Words | – | Free | 100+ | Sep 20, 2026 | Compare |