Monyx: Stop Nail Biting
Habit reversal, 21-day plan
Free · In‑App Purchases · Designed for iPhone. Not verified for macOS.
Unlearn the gesture in 21 days with the HRT method. One lesson a day, your triggers in plain sight, your real regrowth date. 3 days free.
You do not bite your nails because you lack willpower. You bite them because your hand goes up without you.
92% of nail biters say they never see the gesture coming. That is the whole problem, and it is why deciding to stop has never been enough. Monyx works on the gesture itself: noticing it, logging it, replacing it.
THE DAILY PACT
Every morning, sign your pact by holding your finger down for three seconds. Every evening, answer “Pact kept” right from the notification, and your day is validated. Your calendar fills up, kept days link into a streak, and 19 badges mark your milestones.
THE METHOD
21 days of Habit Reversal Training, the behavioural method with the most evidence behind it. One lesson a day, one minute each, one exercise to try before evening. Each day unlocks once you have done the one before.
Week 1, see the gesture. Week 2, replace it. Week 3, lock it in.
TWO TAPS ON THE BACK OF YOUR IPHONE
The urge rises. Two taps on the back of your phone and it is logged, without opening the app, without taking your eyes off what you were doing. That is the whole point: a log that costs nothing is a log you actually keep.
After a few days, your Stats show what you could not see. Your urges cluster around two or three situations, not everywhere. You stop fighting all day and start defending a few precise moments.
YOUR NAILS, IN PHOTOS
One photo a week, always framed the same way, with an alignment overlay so the comparison holds. A nail grows about 0.1 mm a day. It does not show tomorrow. In two months the difference jumps out at you.
WHEN THE URGE HITS
Make a fist and follow a guided breath: 4-7-8, in for 4 seconds, hold for 7, out for 8, or 5 minutes of coherent breathing. Almost every urge passes in under two minutes, whether you bite or not. Every wave you ride out teaches your brain that it ends without going through your mouth.
AND IF YOU SLIP
One bad evening costs a few days on one finger. The spiral that follows costs months on ten. Monyx logs the slip as a data point, not a verdict, and asks what set it off. The people who make it are not the ones who never slip.
YOUR DATA STAYS ON YOUR IPHONE
No account, no email, no password. Everything you log stays on your device and syncs only to your own iCloud. We have no analytics, no advertising and no third parties. You can erase everything from the app, for good, in two taps.
Monyx is not a medical device and does not replace a healthcare professional.
FREE
The daily pact, your calendar and badges, the card of the day, your streak, unlimited logging, your millimetres of growth, and one photo a week.
WITH PREMIUM
The full 21-day program, your trigger analysis, one photo a day and the emergency Breathe button. 3 days free, then a yearly or monthly plan. Cancel anytime in your iPhone settings.
A question, an idea, a bug: hello@getmonyx.app, we answer.
Terms of Use: https://getmonyx.app/terms.html
Privacy Policy: https://getmonyx.app/privacy.html
Ratings & Reviews
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The daily pact is here.
• Every morning, sign your pact by holding your finger down for three seconds
• Every evening, answer “Pact kept” right from the notification: your day is validated
• The new Progress tab: your calendar of validated days and 19 badges to earn
• Breathe now offers 4-7-8 breathing and 365 coherent breathing
Also in this version:
• A livelier home screen, and animations everywhere
• Slide your finger to compare before and after
• Photo timeline thumbnails no longer spill over
The developer, LUC BRUNNARIUS, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- LUC BRUNNARIUS
- Size
- 5.6 MB
- Category
- Health & Fitness
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - Mac
Requires macOS 14.0 or later and a Mac with Apple M1 chip or later. - Apple Watch
Requires watchOS 10.0 or later.
- iPhone
- Languages
- English and French
- Age Rating
13+
- 13+
- Infrequent
Medical Treatment information
Contains
Health or Wellness Topics
- In-App Purchases
Yes
- Monyx Premium Annuel $34.99
- Monyx Premium Mensuel $4.99
- Copyright
- © 2026 Luc Brunnarius EI
