# Subscribing to your cycle forecast

HealthLog can publish your cycle forecast as a calendar subscription, so the
next few periods show up in the calendar app you already use. The feed is
computed fresh every time your calendar app asks for it; HealthLog stays the
only place the data is kept.

## Turning it on

Open **Cycle**, then **Settings**, and find **Calendar subscription**. Before
the button, the card says what it means: your calendar provider stores the
dates on its servers, and turning the subscription off later does not remove
copies it already holds. HealthLog asks you to confirm it is you (a password or
passkey) and then shows the link once. Copy it, or use **Open in calendar app**.

Only you can turn it on for your own record. For a managed profile (a child's
record, for instance), its guardian can. Someone you have shared your record
with cannot, whatever level of access you gave them: the feed puts your dates
in their calendar provider's cloud, and that is your decision alone. It is
managed on the web; the iOS app shows where to find it.

## Adding it to your calendar

- **Google Calendar:** Other calendars, From URL, paste the link. Google
  refreshes subscriptions on its own schedule, roughly every 12 to 24 hours.
- **Apple Calendar:** on a Mac, File, New Calendar Subscription. On iPhone,
  Settings, Calendar, Accounts, Add Account, Other, Add Subscribed Calendar.
  Apple lets you choose how often it refreshes.
- **Outlook:** Add calendar, Subscribe from web, paste the link. Outlook
  refreshes every few hours.

## What the feed shows

- The next period and, once three cycles are logged, a few after it (three
  by default, up to six). Each event covers the whole window the period may
  fall in, and the window widens the further out it is. The list stops itself
  where a date would be more guess than estimate (beyond about ±10 days, or
  half a cycle).
- Optionally, your past cycles (up to twelve).
- Optionally, when your goal is trying to conceive, the estimated fertile
  window of the next cycle. It is an estimate, not a contraceptive method.

Titles are discreet by default: each event is a dot and the calendar is called
"HealthLog". Descriptive titles name the period instead. Events never carry
symptoms, notes or any other detail of your log.

When a period is later than its window, the feed shows no forecast until you
log it, instead of guessing a new date. With predictions switched off, only
past cycles appear (if you chose to include them).

## Rotating and turning off

**Rotate link** replaces the link; calendars using the old one stop updating.
**Turn off** ends the link. In both cases, remove the old subscribed calendar
in your calendar app too: what it already fetched stays there until you do.