All work

Proof

2026sourdough planner, iPhone

Proof — the app on an iPhone

Bakes to a time, not to a recipe.

For home bakers, on iOS 26. Sourdough takes thirty hours and recipes count fixed hours. Proof plans every stage backwards from when you want to slice, moves the plan around your nights, and ends bulk fermentation by measured rise.

The prototype in use, 26 seconds
Today as the jar, with the three decisions
Today as the jar, with the three decisions

Every stage planned back from slicing.

The screen is the jar. Today fills with the starter up to its real rise; the tan band marks where it stood right after feeding.

Plans move around your nights. Shaping that would land in quiet hours gets a warmer bulk instead.

Rise, not the clock. Bulk ends at 50–75 % measured in a small jar, not after a fixed time.

Today: the screen fills with sourdough starter up to its rise, 2.1 times; it stays at its peak until 10:00, so the levain is built before then.
Today
New bake sheet: ready to slice on Saturday at 12:30, two loaves, kitchen at 22°, quiet hours on.
New bake
Plan: shaping would land in quiet hours at 23:10; the proposed fix, bulk at 25 °C, moves shaping to 22:15.
Plan
Bulk ferment: the dough has risen 22 % since 18:00, charted against the 50–75 % target band.
Bulk ferment
Log rise: a jar reading of 136 ml typed on the iOS decimal keypad, 36 % rise.
Log rise
Lock Screen Live Activity: bulk ferment at 36 %, 50 % expected around 21:30.
Lock Screen
Bake log: sliced at 12:35, five minutes after the plan; next time Proof plans 3 h 35 min of bulk.
Bake log

Hairline numerals for a product about timing.

SF Pro and SF Pro Rounded, as on iOS 26, with every time set large and thin. A clickable prototype in HTML with the platform’s own transitions; the film above is recorded from it.

The bake is a sample and the baker is invented.

Thirty hours on one axis, from a ripe starter to slicing
Thirty hours on one axis, from a ripe starter to slicing

Dmytro Dintsen
Senior product designer

Let’s make
something good.

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