Cryptex: a word on turning drums

A puzzle tube from the films

Cryptex makes a word spelled on 5 to 8 drums your passcode, with drums of letters, or of letters and numbers.

Picture a brass tube made of rings, each ring engraved with the alphabet, the kind that guards a scroll in an adventure film. You turn each ring until your word lines up across the tube, then pull the cap. If the word is right, the rings seat one by one and the cap slides free. If it isn’t, the cap rattles and the drums spin away to new letters, so your last try doesn’t stay on show.

Your word becomes the passcode

This is the part to read before you choose it. Choosing Cryptex or Knock replaces your passcode with the word or the rhythm, and Sealed says first if that removes a decoy or duress passcode.

A string of digits can’t be spelled on drums of letters, so the Cryptex asks for a word, and the word becomes the way in. If your old passcode was digits, the change of format takes your decoy and duress codes with it, and an alert says so before anything changes. The decoy vault page and the duress code page explain what each one does, so you know what you would be giving up.

Drums and symbols

Each drum you add multiplies what a stranger has to try by the number of symbols on it. A drum of letters and numbers holds more symbols, so it multiplies faster. All of that assumes a word nobody would guess, which a real word rarely is.

More drums are narrower, and a cryptex of more than five is drawn a little smaller to fit the screen.

Picking a word

• Not your name, a pet’s name or a place you live. People who know you try those first.
• Not a word that sits on your screen. A wallpaper or an app name gives it away.
• Something you can spell under pressure. You will be turning it with cold hands one day.
• Two short words run together are harder to guess than one long one that people know.

Spelling it in for the first time

1. Open Settings, then Passcode & Unlock, and tap Lock Screen. Swipe to the Cryptex. Nothing you spell there is saved.
2. Choose how many drums and which symbols you want.
3. Tap Use This Lock Screen. If you have a decoy or duress passcode, an alert says first which ones go. Cancel there to keep everything.
4. Spell your word on the drums, then spell it again to confirm.

From then on, Use Password under the drums takes the same word on the keyboard, for the days the drums are slow.

Where Sealed helps, and where it doesn’t

It helps if you think in words, not numbers: a word on drums is easy to remember and slow to guess. Cryptex makes a word spelled on 5 to 8 drums your passcode, with drums of letters, or of letters and numbers.

It doesn’t do these things:

• Keep your old passcode. Choosing Cryptex or Knock replaces your passcode with the word or the rhythm, and Sealed says first if that removes a decoy or duress passcode.
• Add strength beyond the word. Every lock screen style is another way to enter your passcode, so it changes how you enter it and not how many combinations it has.
• Guard a word that is easy to guess. A name or a favorite team falls quickly. See how long a code takes to guess.