4.4 KiB
Design
Status: Current
Owner: _null
Last reviewed: 2026-08-18
Governs: docs/design/**, the design tokens in core/designsystem, and the product's
tone and interface copy
Review trigger: Any new user-facing screen or state; any change to the colour or
type tokens; any change to notification copy or to a privacy or
fertility disclaimer
Where the detail is
The screen-by-screen specification and the actual words are
../planning/PRODUCT_PLAN.md, and they are not
repeated here — a second copy of interface copy is how two versions of a
disclaimer come to exist.
| Subject | Section it owns |
|---|---|
| Onboarding, seven screens, with copy | §19, §56 |
| Navigation — four tabs | §20 |
| Today screen and its six dynamic states | §21, §22 |
| Period logging, period end, spotting | §23, §24, §25 |
| Calendar states and markers | §26 |
| Insights | §27 |
| Notification modes, types and flow | §28, §29, §30 |
| Incognito launcher | §32 |
| Look and feel, visual direction, colour, typography, motion | §37–§41 |
| Artwork | §42 |
| Accessibility | §43 |
This document holds what governs those: the tone, and the rules that decide an argument the specification did not anticipate.
Tone
Calm, private, intelligent, adult. The app is a good utility with warmth — it is not clinical, not childish, not gamified, and not stereotypically feminine as an identity. It never celebrates a period and never alarms about one.
One paragraph, and it settles most small arguments: the app speaks like someone competent who is not making a fuss. "Your period is late!" is out. "Not yet?" with an updated forecast is in.
Four rules that decide the arguments
1. The number is the hero. The forecast dominates the Today screen — §38. Anything competing with it for attention is wrong, including anything of ours.
2. Nothing asserts certainty the model does not have. A window and a confidence label, never a bare exact date presented as fact. "Estimated ovulation", never "you are ovulating today". Fertility copy carries the not-contraception line wherever it appears.
3. State is never colour alone. Confirmed period is a solid fill, predicted is dotted or outlined, fertile window is a ring, ovulation is its own small marker — distinguishable in greyscale, because that is also what makes them distinguishable to a colourblind user and to a screenshot in a bug report. Predicted and confirmed days must never look identical.
4. Ads never touch a health action. No banner in onboarding, in the period-start confirmation, in the period-end confirmation, or between steps of a health workflow — and never an interstitial after logging (§33). Banner space is reserved in the layout so a failed ad does not move the content.
Colour, in one line each
The palette is §39; the constraints on it are:
- Not pink as the whole identity. Deep plum, muted berry, soft lavender, warm cream, charcoal, muted sage/teal.
- Period state is a sophisticated berry or plum — never graphic blood-red.
- Fertile window is muted teal or sage — never bright green, which reads as safe and this app must never say that.
- Everything goes through Material 3 colour roles and centralized tokens in
core/designsystem. No hard-coded colours in a Composable — the guard is that a colour literal outside the token file is a review failure.
The states most often left undesigned
Designed here on purpose, because they are the two most people meet first:
- Empty — no periods logged yet. It has to make the next action obvious rather than apologise.
- Learning — one or two cycles recorded. The app says it is still learning rather than showing a confident forecast it has not earned. "Getting to know your pattern", not a percentage.
Include the rejected version
For any decision that was genuinely close, record what was not chosen and why.
Without it the same option is proposed again every few months and re-argued from
nothing. The first entries belong to whoever makes those calls; the
specification's Avoid: lists are already a partial record of them.
What does not belong here
- How it is built —
../architecture/README.md - Scope and audience —
../planning/PROJECT_PLAN.md