# Fortuity Cycle: the cycle tracker two people use.

Simple tracking on one side (one tap starts a period, five symptoms, honest predictions) and a
Support Loop on the other: she invites one person by link, chooses exactly what that person sees,
and can end it in a tap. STATUS: iPhone, in INVITE-ONLY TESTFLIGHT. There is no App Store listing and
no Android app. Nothing is charged and no price is published. This file never claims a shipping
feature that is not shipping.

## What it is for

Logging a period was solved years ago. What was not solved: how much setup stands in front of the
first log, how confident predictions pretend to be, and the fact that the person who wants to help
has no idea what week it is.

## Shipped (iPhone, invite-only TestFlight)

- One tap starts a period, one ends it. A closed set of five symptoms and nothing else.
- Predictions from her own cycles after three are logged; before that it uses a typical 28-day
  cycle and says so plainly.
- Every prediction carries a plus-or-minus rather than a single confident date.
- Apple Health read and write, so the record is useful on day one and stays hers if she leaves.
- The Support Loop: an invite link per person, a per-person choice of what is visible (phase only,
  or phase and symptoms), and one-tap revocation.
- The invited person needs no app and no account: the share opens as a web page.
- A supporter who does install the app can accept an invite there and choose a delivery
  preference for themselves.

## Not shipped, and stated as such

- Automatic notifications. Delivery is switched OFF in the service (`LIVE_DELIVERY = false`); the
  app previews what a notification would say and sends nothing. Going live is a separate,
  ungranted decision.
- App Store distribution and Android.

## Not built, on purpose

- Fertility and ovulation output is OFF by default. This is not an FDA-cleared device and it is
  not in the contraception lane.
- No pregnancy mode, no conceiving coaching, no community, no content library, no AI chat, no
  horoscopes. Restraint is the product rather than a gap.

## Privacy, precisely

- Cycle data stays on the phone by default. The service has no endpoint that takes a general
  upload of the log; what reaches a server is the share surface she deliberately creates.
- A share token resolves to ONE person-object, never to an account-wide query. Enforced by a decoy
  tenancy test with a positive control, so a renderer that outputs nothing cannot pass vacuously.
- Cycle data never goes to a cloud language model, never to a third-party analytics SDK, never to
  an advertising SDK, and is never sold or brokered. In-app analytics is a closed vocabulary of
  feature ids, never content.
- The marketing website measures visits with consent-gated privacy-first analytics. That is the
  website, never the app and never cycle data.

## How this compares (sourced, 2026-07-26)

Flo and Clue are both far larger and BOTH ALREADY OFFER PARTNER SHARING, so sharing itself is not
the differentiator; its shape is (per person, revocable in a tap, no app needed on their end, and
the only reason anything leaves the phone). Flo states "over 420 million people" use its app; Clue
states it is "trusted by millions in over 190 countries" and that data is protected by EU privacy
law. Neither publishes a subscription price on its website. Full table with links:
https://fortuitycycle.com/#compare

## Pricing

Nothing is charged and no price is published. When one exists it will be posted on the site before
any charge, with no card on file and no renewal to discover.

## Limits, stated plainly

- Invite-only TestFlight on iPhone only; no App Store listing, no Android.
- No automatic notifications yet.
- Fertility and ovulation output off by default, deliberately.
- Five symptoms, not an exhaustive taxonomy. The larger apps are genuinely better at breadth.
- It describes and never prescribes. Not medical advice, not a medical device.

## More

- Capability inventory with statuses: /capabilities/
- Privacy notice: /privacy
- Comparison with sources: /#compare
- Home: /

Last revised 2026-07-26.