InkBlot Duo

InkBlot Duo is a studio for folded ink blots: ink on paper, the page folded over, and the surprise when it opens. The ink is real in every way a screen allows. It pools, soaks in, runs into the colour beside it, squeezes out between the pages and is drawn into veins as they part. No two prints are ever the same.

ANY INK, AS MUCH AS YOU LIKE A rack of sixteen inks, from India black and sepia to saffron, viridian and ultramarine, with water beside them. Tap an ink again to thin it, or thin it again to a pale wash. Mix your own in the dish from any inks on the rack, and keep them. There's no limit on how much goes on the sheet, or how many colours.

A DROPPER, AND WHAT A HAND CAN DO WITH ONE Touch the paper and a drop falls. Hold, and it swells to a pour. Set off at once and the dropper dribbles a line; flick it and it spatters. Draw two fingers across wet ink to blow it along, as through a straw. Drop water into ink and watch it bloom. Ink goes anywhere: either page, or right in the crease.

FOLD, RUB, PEEL Fold the page over and the pages press together. Rub the folded sheet and the ink is pushed where your finger goes. Then peel it slowly, and the ink is drawn into long veins; or pull it open, and it tears short. The print is made as the page lifts, at the pace of your hand. Folded too soon? Unfold it, and the ink is as it lay. Add more and fold again, as often as you like.

MADE FOR THE DUO On iPhone Duo the sheet fills the inner display with its crease on the fold. Close the phone and you've folded the paper; the outer display is the back of the sheet, the ink showing through, and you rub it with your thumb. Open the phone and the page lifts with it, the ink drawn into veins as it goes: slowly for long ones, quickly for short. Everything works on any other iPhone and on iPad too, by folding the page on screen.

A DRAWER FOR EVERY PRINT Every print is kept, on your device, the moment the pages part. Give it a name (what do you see?), share the whole sheet or just the blot, or come back to it later.

AND A GAME, IF YOU WANT ONE Nine pencilled shapes to fill, from a bow tie to a beetle, with a handful of drops each. A rubber stamp says how close you came.

• Sixteen inks, water, three strengths, and any colour you mix • Drop, pour, dribble, spatter and blow • Rub the folded sheet; peel slowly or pull it open; undo a fold • Two papers, white or ivory; dry the sheet to work over it; tilt to let ink run • Every print kept in the drawer; share the sheet or just the blot • Made for iPhone Duo's hinge; at home on every iPhone and iPad • VoiceOver actions for everything a gesture does; Reduce Motion; sounds and haptics of paper and ink • No ads, no accounts, no tracking. Nothing leaves your device.

Discovery signals