Who am I? The forehead guessing game

It is the forehead guessing game, a party game usually called "Who am I?" in Britain. One player cannot see a word that everyone else can read: a name on a sticky note, or here a card on a phone. In the paper version the guesser asks yes or no questions and the group only answers. In the phone version the group describes the card against a timer, without saying the word, and each right guess scores a point.

In Australia the same idea is known as celebrity heads. Phone apps such as Heads Up! play a timed version with a tilt to score. This page is a separate browser game and has no link with that app or its makers.

No association or publisher sets official rules for the phone version. The timer, the tilt, the teams and the one point per right word on this page are the site's own choices, explained below.

A round begins when someone presses Start, which opens a full-screen stage on the phone. From there, every round follows the same steps.

1. The guesser holds the phone to their forehead, screen facing the group. With tilt switched on, play begins once the phone has been held upright and still for 0.6 seconds; otherwise someone taps Go.
2. A 3 seconds countdown gives everyone time to settle, then the first card appears.
3. The group describes the card while the guesser calls out answers. To score a right guess, tilt the phone down so the screen faces the floor; tilt up to pass, with the screen towards the ceiling.
4. The Right and Pass buttons on the screen always work as well, and on a computer the arrow keys do the same job.
5. With sound on, the last 5 seconds tick audibly, and a buzzer ends the round.

A tilt counts once the screen has turned more than 40° away from upright. The next one counts only after the phone has come back within 20° of upright, so a single nod never scores twice.

Whatever card is showing at the buzzer goes on the list as passed. That list of words then appears, and tapping a word switches it between right and passed, which corrects a tilt the phone misread. Each right word earns one point, and passing costs nothing.

The round timer offers 30, 45, 60, 90 and 120 seconds, starting on 60 seconds. Pause holds the clock during an interruption, and Stop the round ends it early with the cards played so far counted.

Between 1 and 6 teams can play, each taking 1 to 10 rounds in turn. A new game starts with 2 teams and 3 rounds each.

Setting the teams to 1 keeps everyone in one group. The phone then goes round the room, with a new guesser each round, and the score belongs to the whole group.

With more than one team, the screen names the team whose turn comes next, and one of its players holds the phone while teammates give the clues. Whether rival teams may call out answers is for the table to settle, as the game counts only what is tilted or tapped.

A scoreboard keeps every team's points round by round, with a total. After the last team's final round, the final scores show the winner, or a tie between the teams level on points. Teams and rounds stay fixed until that game ends or a new one begins.

At the starting settings a game holds 6 minutes of guessing, plus the countdowns and the time spent checking each list of words.

The game holds 10 decks written for British players, 523 cards in all. Every deck except the children's is switched on at the start, which puts 471 cards in play.

The Famous people from history deck holds only people who have died, such as Shakespeare and Isaac Newton. It therefore never dates, and it never puts a living person's name on anyone's forehead.

The Fairy tales and legends deck keeps to characters in the public domain, from old stories and classic books, such as Robin Hood and Maid Marian. No deck contains brands, films, television shows or characters owned by a company. Living stars, classmates or a theme for the evening can be typed in as your own words instead.

These categories also answer the usual question of what to write on the cards: an animal, a job, a dish, a place, a person or a character. No card runs longer than 32 characters, so each one fits in large type on a phone held sideways.

Cards never repeat until every card in play has been shown, and then the pile is shuffled again. The shuffle uses the browser's cryptographic random numbers (W3C).

The Act it out deck turns the game into charades on your phone. Its cards are actions, such as brushing your teeth, riding a bike and ironing a shirt, which the group can mime instead of describing.

In classic charades one player acts out a word or title in silence while their team guesses. Here everyone who can see the screen performs at once, and the player holding the phone does the guessing.

The game cannot tell whether a card was acted or explained, so the mix is a house decision. Some tables mime only the action cards and talk through the rest. The deck also works on its own, with every other deck cleared.

Each player wears a name on a sticky note on the forehead without seeing it, then asks yes or no questions to work out who they are. The Scouts describe their version this way, with everyone taking turns to ask (Scouts).

Their advice is to start broad and then get more specific, with questions such as "Am I alive now?" or "Am I a singer?". Their variations move the note to the player's back or have players work in pairs.

Girlguiding describes a Brownies version with labels on their backs, in which each name has a partner, such as Jack and Jill, and only questions with a yes or no answer are allowed.

Because of the notes, many people know it as the post-it note game, after a brand of sticky note owned by 3M. The game itself needs only paper and a pen.

Printable cards save the handwriting. The print option deals a sheet from the decks and words chosen above. It holds 12, 24, 36 or 48 cards, 24 unless changed, shuffled and set two to a row with 12 on each A4 page. The words are large enough to read across a table, and dashed lines show where to cut out each card.

A Christmas who am I game puts a festive theme on the cards, such as reindeer, crackers, carol singers or characters from Christmas stories. The Scouts also suggest a Christmas or Halloween theme for their paper version.

The built-in decks are not seasonal, so a theme is typed into the settings, one word per line, with Play only my words ticked. Without that tick the theme mixes with the chosen decks.

On Christmas Day or Boxing Day it works as a family game across generations. The For children deck keeps the words simple for the youngest players, and the buttons spare anyone who finds tilting awkward.

As an icebreaker at work or on a hen do, the teams setting splits the room and the scoreboard does the counting. Guests' names and shared jokes can join the cards the same way, and they never leave the page.

For a party game built around presents rather than words, the Christmas dice game runs a gift swap on one phone.

In a classroom the yes or no version becomes a speaking exercise. Teacher notes from the British Council say it works as a process of elimination and practises question forms and useful vocabulary (British Council).

In England, the National Curriculum covers the same skill under spoken language. Pupils in years 1 to 6 are to be taught to "ask relevant questions to extend their understanding and knowledge" (Department for Education).

For learners of English, the British Council's English Online blog describes a timed version called Mind Reader. A famous name goes on a teammate's forehead, and the others describe it without saying the name, within 30 seconds.

On a classroom screen the arrow keys answer, and the own words box takes a week's vocabulary or spelling list. The printed sheet gives a set of cards for each group table. The same words can then turn up in a word grid game of hidden words.

The game runs in the browser, with no download and no app to install, and the phone's motion sensors report each tilt to the page (W3C).

On an iPhone, Safari asks once for permission to use motion and orientation data, a request Apple introduced with iOS 13 (Apple). If permission is refused, the two buttons on the stage answer instead. Android phones pass the sensors to the page without a prompt.

A computer has no motion sensor, so the buttons or the arrow keys answer there. During a round the screen stays on wherever the browser supports Screen Wake Lock (W3C).

On Android the stage goes full screen and turns to landscape. A web page cannot turn an iPhone, so the game asks the player to hold it sideways. Vibration works on Android only.

The page link keeps the chosen decks, round length, teams and rounds, so a shared link opens the same game on another phone. Own words never go into the link, are never stored and are never sent anywhere. They stay on the page until it is reloaded, and nothing is saved in the browser.