Luna Luna has been supporting women's menstrual cycles for over 20 years! It's now downloaded over 22 million times!
This free menstrual cycle management app is packed with information women care about, like your next period, ovulation date, fertile/unfertile periods, recommended diet times, and daily health information!

◇◆Overview◆◇
When your period comes, simply enter your period date.
You'll then receive notifications about your physical and mental health, including your next expected period date (predicted period date), expected ovulation date (predicted ovulation date), optimal diet times, and skin condition!
The more you record your period dates, the more accurate the predictions become based on your cycle! This convenient health management app for women lets you easily predict your period.

◇◆Luna Luna's Unique Algorithm◆◇
Luna Luna offers a unique ovulation prediction algorithm developed based on data accumulated over 15 years. (*Patented)
We will notify you of your expected ovulation date and fertility based on your menstrual cycle!

◇◆Luna Luna is also available at medical institutions!◆◇
Data recorded with Luna Luna can be used at gynecological and obstetrician-gynecologist appointments nationwide.
The number of medical institutions that have implemented Luna Luna Medico is expanding nationwide!

◇◆Features of the Luna Luna App◆◇
- Easily display your next period date with a countdown on the home screen. Open the app to see your exact expected period date, ovulation date, and high/low fertility at a glance!
- A recording button appears on the home screen when your period approaches. Easily record your period with just a tap.

・Your menstrual cycle and your physical and mental health are intimately connected. Get five indices (advice) for your "Body," "Mind," "Diet," "Skin," and "Beauty" that are updated daily, 365 days a year, based on your menstrual cycle!
・Plan ahead by checking your expected period and ovulation dates on the calendar! You can check up to three months in advance, so it's great for planning trips and more.

◇◆Basic Features◆◇
1. Period Prediction/Ovulation Prediction
Based on the start dates of your previous periods, your next period and ovulation date are predicted and notified.

2. Fertility Prediction
Calculate your menstrual cycle based on your previous periods and predict your current fertility (days when you're most fertile/unfertile).

3. Daily Updated Index (Health Advice)
Hormonal changes during menstruation, such as premenstrual irritability, swelling, and rough skin during menstruation, are closely related to your physical condition. Luna Luna's index (health advice) will notify you of your physical and mental state every day.
The content changes 365 days a year, so checking it every morning is also useful for planning your day.

4. Calendar
Check your next expected period, expected ovulation date, and fertile period on the calendar. Tap the date to conveniently record your physical condition for that day.
You can also record plans such as "hospital visits" and "dates."

5. Health Management
Easily record your daily health.
Easily record your physical condition and mood during your period, as well as menstrual pain, menstrual flow, and irregular bleeding, with just one tap. This allows you to notice any discomfort or changes and prepare in advance.
Having a record is also useful when visiting the doctor.

◇◆Providing Services for Every Life Stage◆◇
Women's lifestyles are unique, depending on their age and environment.
Luna Luna offers various stages and modes to meet changing needs.

・Junior Mode
This mode is for elementary and junior high school girls and can be used from before their first period.
Pre-menarche provides an estimate of when menarche will occur. Even after menarche, it supports irregular periods and helps you manage your expected period date and cycle.
We also provide columns on first periods tailored to each age. This mode has a simple and cute design.

・Pill (OC/LEP) Mode
This mode is for women taking the pill.
Daily medication records and reminders help you take your medication.

・Pregnancy Stage
This stage is for women hoping to become pregnant.
"Friendship Day" is Luna Luna's proprietary ovulation prediction algorithm, developed based on data collected by Luna Luna for over 15 years. (*Patented) Pinpoint your most fertile days.
*"Friendly Days" is a Premium feature.

- Pregnancy Stage
During pregnancy, use our sister app, "Luna Luna Baby"!
Receive daily updates on your baby's condition.

- Aging Mode
This mode is for those experiencing menstrual cycle irregularities due to age or those concerned about pre-menopause and menopause.

◇◆Premium Course Introduction◆◇
Enjoy even more comprehensive support features than the free app!
We introduce some paid features. *Subscription is optional.
- "Friendly Days" with high fertility
- Constipation and Communication Index
- Extended period and ovulation predictions
- Ask the Teacher
- Self-Check
- Partner Sharing
- Health Reports and Data Analysis
- Ad Banner Removal
*Ad banners within some services will not be removed.


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◇◆Contact Us◆◇
While our staff appreciates your valuable feedback and opinions, we are unable to respond directly or individually to reviews.
We apologize for the inconvenience, but if you have any issues, inquiries, or requests, please contact us by launching the app > clicking "Menu" in the bottom right > clicking "Customer Support" at the bottom of the page > "Help/Inquiries."

(Thank you for your many reviews. Your reviews are greatly appreciated by our staff.)

If you are unable to launch the app, please contact us using the form below.
https://sp.lnln.jp/brand/terms/contact

◇◆Other Notes◆◇
[1] The default installation destination is the device itself.
If your device's memory is low, installation may not be possible.
In this case, we apologize for the inconvenience, but please free up space by transferring files from the device to an SD card, etc., before installing.
(After installation, you can manually move the app to the SD card. Change this setting in your device's "Settings.")

[2] Depending on the sync settings of your device and computer, the icon may disappear from your device's home screen after installing the app and syncing with your computer. We apologize for the inconvenience, but if this happens, please reinstall the icon and check your sync settings.
(The app will not be uninstalled automatically, and your data will likely remain even in this case, but please check.)

[3] For users of the "+HOME" app
After updating the app, you may be unable to open the icon displayed on the home screen of the "Luna Luna" app.
We apologize for any inconvenience this may cause.
Please follow the steps below to open the app from the home screen icon.

*Please be careful not to delete the app.
1. Delete the app shortcut from the home screen.
2. Re-create the shortcut on the home screen from the app list.

*Download figures are as of June 2025.