Calendula Period & Cycle Tracker App

Overview

Calendula is a period and cycle tracker for adults who want a calm, private one: the current cycle drawn as a bloom of days on Today, a calendar told apart by shape, a day logged in a few taps, and patterns drawn only from the person's own logs. Every estimate says it is one, and none of it is birth control.

The look is white and plain: ink for every choice, calendula orange only for period days and a clear blue only for the estimates, so each colour means one thing on every screen. A clinic, a women's health brand or a creator can ship it as their own: the short reads, the symptom lists and the plans are data.

Key features

• Today: the cycle as a bloom, one petal a day, with the next period's estimate and its range

  

• Calendar: logged period days and the estimated next period and fertile window, each by its own shape

  

• Log a day: flow, pain and how strong, symptoms, mood, sleep and a private note

  

• Insights: cycle lengths with their average, what shows up before a period, symptoms by phase

  

• Ask your logs (AI): answers with numbers from the user's own cycles, and the cycles they came from

  

• For your doctor: cycle dates and lengths, heavy days, pain and flagged notes, shared as text

  

• Share with a partner: they see the phase, the next period and period days, never symptoms or notes

  

• A symptom across cycles: every day it was logged, lined up on the first day of each period

  

Screens

Welcome, five onboarding steps and a first estimate built from the answers, the paywall, Today and its phase sheet, the calendar, a day's log, Type it, Period dates, Insights, all cycles, a cycle, a symptom across cycles, Ask your logs, For your doctor, Share with a partner, Join with a code and a partner's view, You, Settings, Reminders, Back up with email, six short reads, When to talk to a clinician, Privacy, Terms and About: 33 screens, light and dark.

AI and backend

Supabase keeps each person's logs, settings and questions, readable only by their owner, with the rules in the database: one log a day, checked values, share codes that expire after 7 days and work once, and a partner who reads only a published view. Everyone starts as an anonymous user; an email with a 6-digit code keeps the logs on a new phone. One Edge Function runs two AI tasks with Gemini against a daily allowance: Type it (a sentence read into today's log) and Ask your logs (Plus). Questions about a condition, medication, contraception or the chance of pregnancy are refused before the model, and nothing is sent until the user allows it once.

Monetisation

Calendula Plus through RevenueCat, yearly with a 7-day free trial or monthly: twelve cycles and the patterns in Insights, Ask your logs, For your doctor and partner sharing. Logging, the calendar, the estimates, reminders, Type it and export stay free.

Health and privacy

Calendula is not a medical device and does not replace professional care. Its estimates come from the user's own logs and are not for birth control; it names no condition and judges no value, and When to talk to a clinician lists the signs to see a clinician and to get urgent care, from NHS, CDC and NIH patient pages. No ads, no account needed to start, export and Delete my data free.

Setup

It opens on a sample person ten cycles in, with no setup. Connect Supabase for accounts and backup, add the Gemini key for Type it and Ask, then RevenueCat for Plus. Reminders are local notifications.