Duel: a two-player question game

Before the face-off: names, mode and theme

Duel is built for exactly two people: the app will not start a match with one player more or one fewer. The heart of the game is played out loud, face to face; the phone is there to deal out the secrets, keep them hidden and deliver the verdict. On a single phone, type in both names and choose:

• Mode: Words (be the first to guess) or Numbers (estimate better than your opponent).
• Category for Words, including Cities, Animals, Food, Jobs, Objects, Places, Sport, Nature, Actions and Characters.
• A scale for Numbers, each with its own range: Age from 0 to 100 years, Height from 140 to 210 cm, Price from 1 to 500 euros, Temperature from −10 to 40 degrees, Spiciness from 0 to 10, Population from 100 to 10 million, and more besides.

If you leave the category or scale on Random, which is the starting setting, the surprise is twice as big. There is no timer and the app does not count the questions: how many you ask and who goes first is up to you.

Words mode: first to guess wins

1. The app draws two different words from the same category. The phone changes hands: each of you presses and holds to see the word your opponent has to find, then hides it and passes the phone back.
2. You take turns asking questions. Whoever is asked answers only yes or no, thinking about the word they saw.
3. When you feel ready, tap the button with your name on it (“Sophie tries to guess”, for example) and say the word out loud.
4. Your opponent taps Right! or Wrong. A wrong guess costs nothing: you simply go back to asking questions.
5. The first correct guess ends the match. The final screen shows both words, so you also find out how close the other player was.

Numbers mode: the closest estimate wins

1. Each of you secretly receives a number within the range of the scale. The theme and the range are known to both players.
2. You take turns asking questions about the other person’s number. Here the answers can be more nuanced than a plain yes or no, if you both agree.
3. When you are ready, tap the button to move on to estimating: one at a time, in private, each of you types an estimate of the opponent’s number and taps “Confirm and hide”.
4. The app reveals the real numbers, the estimates and how far off each of you was. The smallest gap wins; if the gaps are identical, it is a Tie!.

Sophie versus Tom: two matches in ten minutes

A dentist’s waiting room, a single phone. Sophie and Tom choose Words and the category comes out at random: Animals. Sophie sees “Penguin”, the word Tom has to find; Tom sees “Giraffe”.

1. Tom asks: “Does it live in water?” Sophie thinks about it and says yes. Sophie asks: “Is it bigger than a dog?” Yes.
2. Tom: “Does it have legs?” Yes. Sophie: “Does it live in Africa?” Yes.
3. Tom, impatient, taps his button and says “seal”. Sophie taps Wrong and they carry on with no penalty.
4. Sophie: “Is it taller than a person?” Yes. That is enough for her: she taps her button, says “giraffe”, and Tom taps Right! to confirm. Sophie wins.

Rematch on Numbers, Price scale. Tom has 312 euros, Sophie 47. After five questions each, Sophie estimates 300 for Tom (12 out), Tom estimates 60 for Sophie (13 out). Sophie wins by a single euro.

One phone or two: what changes

On the same phone, the device only changes hands at the secret moments: when the words or numbers are handed out and, in Numbers, for the estimates. The rest of the time it stays on the table. Each game is a single match, after which you go back to the group screen.

In a room, one of you creates it and the other joins with the code or the QR code. Nobody has to look away or pass the phone any more:

• The host chooses the mode and the category or scale in the lobby. In Numbers they can also set the number of rounds: 1, 2, 3 or 5 (3 to begin with).
• Each player sees only what is meant for them on their own screen, the word they will answer questions about or their own number, always behind the “Press and hold to see” gesture.
• In Words, your final answer is typed into the box and sent; your opponent rules it right or wrong on their phone. After a miss, both of you see which word was tried and who judged it, without the correct word being revealed, and then the duel carries on.
• In Numbers, each of you locks in an estimate in private; once both are in, the round verdict arrives. The numbers change every round, and at the end whoever has won more rounds wins. Equal rounds means a tie.

The room works at a distance too: with a voice call open, the questions fly back and forth out loud while the secrets stay on the phones.

Questions that win matches

With words

• Cut the field in half. “Is it bigger than a cat?” or “Would you find it indoors?” rule out half the possibilities; “Is it a lion?” rules out just one.
• Guess when you are down to two candidates. A wrong guess is free, so a guess between two options is worth taking; one between twenty only wastes time and gives your opponent a clue about where you are heading.
• Answer honestly and consistently. If a question has no clear answer (“Is it pretty?”), ask for it to be rephrased: the app does not check the answers, and the game relies on trust.
• Synonyms and details. Agree beforehand whether “tortoise” counts for “turtle”: your opponent is the judge, so better to settle it before rather than argue afterwards.

With numbers

• Halve the range. “Is it more than 50?”, then “more than 75?”: on a scale from 0 to 100, seven yes-or-no answers are enough to pin down the exact number.
• Set a question limit. That is exactly why: with no limit you would both end up spot on. Three, four or five questions each turn the estimate into a real gamble.
• On huge scales, think in orders of magnitude. With Population, from 100 to 10 million, ask “Does it have at least seven digits?” before getting into the detail.
• Write the answers down. A scrap of paper saying “over 200, under 350” stops you forgetting a clue halfway through.

Couples, siblings and waiting rooms: when it works best

Duel is at its best when there are two of you and time to fill: a couple at a café table, two siblings in the back of the car, a parent and child in a queue or a waiting room. It needs no space and no raised voices, and a match lasts a few minutes. Words also works with children who can already ask yes-or-no questions, because the categories are concrete and familiar; Numbers appeals to anyone who likes to reason things out and do a bit of mental arithmetic.

When you want a change of pace, Tic-Tac-Toe is the quickest break for two, and there are more ideas in our guide to games for two people. If more friends turn up, the yes-or-no questions carry on in Who Am I?.