
68
BU Score
Solid
Once -A special period tracker
✍️ bumetric analysis
“
Once -A special period tracker is an Android app from (주)넵튠 in the Health & Fitness category, currently rated 4.2★ across 22,928 ratings. Initial signal reads as mixed reviews: supporters praise core features while critics cite stability and value gaps.
Our BU Score puts it at 68: Solid (established niche player). For a Health & Fitness app, that means established niche player.
Track changes month-over-month in the Performance section below: live snapshot history and revenue forecast included.
📊 Performance Tracking LIVE
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Rating
—
Reviews
—
Forecast Revenue / mo
—
Snapshots tracked
0
since first record
Range:
💰 Forecast Revenue / mo
MODELRevenue forecast computed from BU's 234 trigger model on each snapshot. Calibrated against ground-truth from 58 verified-revenue apps.
🔬Forecast Breakdown — Why This Estimate?Top 4 of 4 triggers
Our ML model uses 200+ signals from public data. These are the most influential for this app:
| Mid install base (22,928 ratings)METRIC | +$5,500 | |
| Mature app (15y old)METRIC | +$1,500 | |
| Good rating (4.2★)METRIC | +$800 | |
| Ad-supported / freemiumMETRIC | +$600 |
METRIC = structural app data · REVIEW = mined from user reviews · ✓ VERIFIED = Stripe-verified anchor (TrustMRR)
📈 Reviews Growth
LIVECumulative review count from first BU snapshot. Each point = a tracked update.
⭐ Rating Trend
LIVEAverage rating evolution. Updates with each new review batch.
🗓️ Snapshot Timeline
HISTORYEach bar shows a tracked update and the metric delta from the previous snapshot.
App Specs
🔐 Own this app? Claim & verify MRR →🔖 vVaries with device📂 Health & Fitness💰 Free📺 Ad-supported💎 IAP $0.99 per item🚀 Launched 2010 (15y old)
📝 About this app
For the all women who need menstruation recording calendar
For the all women who need caring dairy for irregular menstrual pain and menstrual cycle
For the all women who want to know the fertility, ovulation, contraception and probability of pregnancy through calendar
For the all women who annoys marking menstruation and contraceptive pill on the calendar every time.
For the all women who secretly record the symptoms of her body on the calendar.
--
Must Have! Menstrual cycle management app, Once
<b>[ We fulfill the standard of menstrual cycle management app!]</b>
<b> ** Menstrual calendar being more accurate as more as you use! </b>
It smartly calculate your menstrual cycle that was really hard to expect when the menstrual pain will come.
In the menstrual calendar, you can see the expected menstrual date, ovulation day which has high probability of pregnancy, fertility and taking contraceptive pill at a glance,
In the calendar history, you can see menstrual cycle at a glance.
<b>** Taking care of ovulation date and fertility!</b>
You can easily recognize the ovulation date, fertility and expected menstrual date
at a glance, so you can take care of yourself more preciously.
<b> ** Scientific calculation of probability of pregnancy! </b>
Based on the ovum survival period for 24 hours and the sperm survival period for 3 to 5 days, the 1 day before and after the ovulation date have high probability of pregnancy. We are displaying the probability of pregnancy as middle in the fertility period.
<b>** The day that needs preparing of body and mind, prepare in advance! </b>
The day, for not to be embarrassed! In the needful situations(expected menstrual date/fertility with high probability of pregnancy / ovulation date etc when you want), they let you know the day in advance with alarm and sensible messages.
<b>** Save my precious every day records simply!</b>
Save your data in more easier and simpler way than diary.
If you sign up, you can store all the data that you record such as menstrual date, loving date, taking contraceptive pill, memo, auto calculated ovulation date and fertility period!
Although you change your smartphone or install the app again after deleting, you can have data back in the menstrual calendar when you log in!
<b>** Not only the menstrual date but also the secret love date! </b>
You can easily record the condition or symptoms of your body, the starting date of menstruation and menstrual pain.
Once will be my secret diary that even can record the secret loving date!
You don't have to worry about that someone will secretly look your diary because it has a lock function.
<b>** Neat and refined design catching women's mind! 'The pretty app is good to see and also good to use' refined and neat design enhanced the usability of the menstrual calendar.
By simple menstrual calendar, you can see the expected menstrual date and fertility at a glance.
Like your cool diaries on your desk, Check cool designed calender application in your cell phone for your period.
---
<b> * Request permission </b>
WRITE_EXTERNAL_STORAGE
ONES uses the authority of WRITE_EXTERNAL_STORAGE to save data
READ_EXTERNAL_STORAGE
ONES uses the authority of READ_EXTERNAL_STORAGE to load data
GET_ACCOUNTS
ONES uses the authority of GET_ACCOUNTS to improve its web environment.
---
<b> Let's be with Once that always does the best to offer the best service :D</b>
※ You can get a fast response if you send the question to 'once@malang.kr' :)
--
This service includes In-app Purchase items, and a separate fee will be charged for purchase.
Terms of Service : https://bit.ly/38zBlvj
Privacy Policy : https://bit.ly/3iqaZ3g</b>
For the all women who need caring dairy for irregular menstrual pain and menstrual cycle
For the all women who want to know the fertility, ovulation, contraception and probability of pregnancy through calendar
For the all women who annoys marking menstruation and contraceptive pill on the calendar every time.
For the all women who secretly record the symptoms of her body on the calendar.
--
Must Have! Menstrual cycle management app, Once
<b>[ We fulfill the standard of menstrual cycle management app!]</b>
<b> ** Menstrual calendar being more accurate as more as you use! </b>
It smartly calculate your menstrual cycle that was really hard to expect when the menstrual pain will come.
In the menstrual calendar, you can see the expected menstrual date, ovulation day which has high probability of pregnancy, fertility and taking contraceptive pill at a glance,
In the calendar history, you can see menstrual cycle at a glance.
<b>** Taking care of ovulation date and fertility!</b>
You can easily recognize the ovulation date, fertility and expected menstrual date
at a glance, so you can take care of yourself more preciously.
<b> ** Scientific calculation of probability of pregnancy! </b>
Based on the ovum survival period for 24 hours and the sperm survival period for 3 to 5 days, the 1 day before and after the ovulation date have high probability of pregnancy. We are displaying the probability of pregnancy as middle in the fertility period.
<b>** The day that needs preparing of body and mind, prepare in advance! </b>
The day, for not to be embarrassed! In the needful situations(expected menstrual date/fertility with high probability of pregnancy / ovulation date etc when you want), they let you know the day in advance with alarm and sensible messages.
<b>** Save my precious every day records simply!</b>
Save your data in more easier and simpler way than diary.
If you sign up, you can store all the data that you record such as menstrual date, loving date, taking contraceptive pill, memo, auto calculated ovulation date and fertility period!
Although you change your smartphone or install the app again after deleting, you can have data back in the menstrual calendar when you log in!
<b>** Not only the menstrual date but also the secret love date! </b>
You can easily record the condition or symptoms of your body, the starting date of menstruation and menstrual pain.
Once will be my secret diary that even can record the secret loving date!
You don't have to worry about that someone will secretly look your diary because it has a lock function.
<b>** Neat and refined design catching women's mind! 'The pretty app is good to see and also good to use' refined and neat design enhanced the usability of the menstrual calendar.
By simple menstrual calendar, you can see the expected menstrual date and fertility at a glance.
Like your cool diaries on your desk, Check cool designed calender application in your cell phone for your period.
---
<b> * Request permission </b>
WRITE_EXTERNAL_STORAGE
ONES uses the authority of WRITE_EXTERNAL_STORAGE to save data
READ_EXTERNAL_STORAGE
ONES uses the authority of READ_EXTERNAL_STORAGE to load data
GET_ACCOUNTS
ONES uses the authority of GET_ACCOUNTS to improve its web environment.
---
<b> Let's be with Once that always does the best to offer the best service :D</b>
※ You can get a fast response if you send the question to 'once@malang.kr' :)
--
This service includes In-app Purchase items, and a separate fee will be charged for purchase.
Terms of Service : https://bit.ly/38zBlvj
Privacy Policy : https://bit.ly/3iqaZ3g</b>
Profile & Insights
Everything we know — and don't — about this app and its company.
Identification
- App name
- Once -A special period tracker
- Developer
- (주)넵튠
- Bundle ID
- net.android.wzdworks.magicday
- App Store URL
- Open in App Store
- Category
- Health & Fitness
- Content rating
- Not found
- Languages
- Not found
Company
- Website
- assets.adxcorp.kr
- Tagline
- Not found
- Description
- Not found
- Founded
- Not found
- HQ / Address
- Not found
- Employees
- Not found
- Logo
- Not found
Revenue
- Verified revenue / mo
- Not found
- AI revenue estimate / mo
- Not found
- AI annual estimate
- Not found
- ML model estimate / mo
- $1.3K/mo
- Top-grossing rank
- Not found
- All-time revenue
- Not found
- Pricing
- $0.99 per item
Founder
- Name
- Not found
- X / Twitter
- Not found
- Not found
- GitHub
- Not found
- X followers
- Not found
- Public statements
- Not found
Funding
- Total raised
- Not found
- Last round
- Not found
- Investors
- Not found
- Crunchbase
- Not found
- AngelList
- Not found
Press & Links
- Articles found
- Not found
- Listed on
- Not found
- Blog
- Not found
- Press / News
- Not found
Contacts & Socials
- Socials
- Not found
- Not found
- Phone
- Not found
- Contact page
- Not found
- About page
- Not found
📈Ratings growth22,928 ratings+9% lifetimeShow 3-year history estimate ▾
Tracked (1 weeks) Pre-tracking estimate (37 weeks) · model-based, ±5% noise · anchored to release date and current value
Profile is built from iTunes Lookup + developer site scrape + ML revenue model. Empty fields show "Not found" — additional sources (Crunchbase, X, IndieHackers, Acquire.com) coming.
Full revenue analysis
Read the article-style breakdown for Once -A special period tracker: category rank, percentile, growth signal, comparable apps, and how the forecast is calibrated against verified-MRR anchors in this niche.




