The three summary cards
Cycle length is calculated from the number of days between consecutive recorded period starts. Period length is calculated from each saved period range, including its start and end dates. The third card simply counts the period ranges currently stored in the app.
If there is not enough real data for a chart, MiniCycle labels and shows example charts instead. Those sample lines are not your records. Once enough dates are available, the real cycle-length and period-length charts replace them.
Up to 24 recent samples
The charts and their displayed summaries use up to 24 recent samples. Cycle samples are the gaps between starts, while period samples are the lengths of saved ranges. A manual cycle-length or period-length setting does not replace these recorded values in the statistics tab; those settings are used elsewhere for predictions and newly created ranges.
Accurate start dates matter for cycle length, and accurate end dates matter for period length. Correct a mistaken date in the calendar rather than adjusting a setting to make the statistics look right.
What ‘average’ currently means
The interface currently labels the summary as an average, but the implementation uses a median-style representative value rather than an arithmetic mean. With an even number of samples it rounds the midpoint of the two middle values. When there are at least 10 samples, it removes one shortest and one longest value before taking that midpoint.
This makes the summary less sensitive to a single extreme value. It also means you should not try to reproduce the card by adding every point and dividing by the count; that is not the calculation the current app uses.
Storage and limits
The tab performs these calculations on the iPhone. Records are stored on the device by default; if you enable iCloud Sync, a copy is also stored in your private CloudKit database as described in the privacy policy.
A chart can help you notice a change, but it cannot explain its cause or diagnose a condition. If a pattern changes suddenly, repeatedly falls outside your usual range, or comes with heavy bleeding, severe pain, or other concerning symptoms, use the dates as context for a healthcare conversation.
MiniCycle for iPhone
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MiniCycle is built for a clean iPhone period calendar, local records, simple statistics, and a home screen widget.
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