HeySis — iPhone period tracker

https://heysiss.vercel.app
https://apps.apple.com/app/id6786661657
Checked: 2026-09-12
iPhone, iOS 26+, 33 languages
US Premium: $5.99/month or $24.99/year; offers may vary.

HeySis core features will always remain free. Premium is optional and unlocks additional features.

Period diary, symptoms and reminders
Log period days, flow, symptoms and mood, then return to a month of entries instead of remembering everything at an appointment. The diary, calendar and cycle predictions work on your iPhone offline. Period reminders help you prepare. Core features will always remain free; optional Premium adds deeper insights and additional features.

Circle: share how you feel with people you choose
Invite a partner or friends to Circle and choose what to share. A basic status helps someone understand how you feel today; it is separate from handing over your whole diary. Invitations and basic status are free. More detailed member insights and selected interactions require Premium. An invited companion does not need their own paid subscription to join. Sharing needs an internet connection.

A free PDF report for your doctor
Generate the report on your phone. It brings together up to six recent cycles, symptom timing and a recent diary overview, helping you bring recorded dates and patterns to a conversation. The report can include sensitive entries, so preview it before choosing to share. AI conversations are excluded. A report organizes your records; it does not diagnose a condition.

Move period history from calendar screenshots
Choose up to four calendar screenshots at a time. Recognition runs on the iPhone and imports recognizable logged period days. Month and year labels should be visible. It does not import every symptom, note or predicted fertile day, and is not a full backup transfer. Review the dates afterwards; existing filled HeySis entries take priority. Apple Health offers a separate route for supported records. There is no general CSV or JSON file importer.

An AI assistant for questions about your cycle
Ask a question in your own words with your cycle and well-being context, rather than navigating only through charts. Online answers require consent: your message and the relevant context are processed by an AI provider. There is a free message allowance; Premium increases it. The assistant can make mistakes and offers educational support, not diagnosis. You can keep using the diary without enabling online AI.

Apple Health: separate read and write permissions
Import supported records that are already in Apple Health after granting read permission. Writing period flow and selected symptoms to Health is enabled separately. AI conversations and personal notes are not written to Health. Import does not automatically turn on cloud sync or Circle sharing.

Pregnancy and cycle education
HeySis includes pregnancy tracking with weekly information and entries, alongside cycle-phase reading. Basic pregnancy information and logs are free; selected baby illustrations and weight analytics are Premium features. The extended article library also has paid content. App availability and paid access are shown in the current release.

What stays on the phone and what goes online
The diary is stored on the device by default. Online AI, optional cloud sync and Circle are separate network features. There are no in-app ads and user data is not sold. The privacy policy explains service providers, product analytics, permissions and deletion. Local storage is not a claim that every feature stays offline, and HeySis does not claim independent security certification or clinically superior prediction accuracy.