Mac OS Menu Bar App

Stop Biting
Your Nails

Your Mac's webcam watches for nail biting and alerts you the moment it happens. AI-powered habit breaking that actually works.

Get Nail Snitch
One-time purchase. No subscription. 100% offline.
Hands away from mouth — no biting detected
All Clear ✋
Hand at mouth — nail biting detected
Snitched! 🫣
Nail Snitch running on macOS, with a Snap Alert panel reading 'Snitched! Caught you biting'

Nail Snitch lives in your menu bar — always watching, never in the way.

How It Works

1
💻

Install & Forget

Download from the Mac App Store, grant camera access, and you're done. Runs silently in your menu bar from boot.

2
👁

AI Watches

Apple Vision detects your hand moving to your mouth, checks for the curled-finger biting posture, and filters out eating and chin resting.

3
📸

Get Snitched On

An audio alert fires and Nail Snitch snaps the exact frame you got caught in — on your screen for five seconds, then gone. You become aware, you stop.

Everything You Need

📸

Snap Alert

Caught biting? Nail Snitch snaps the exact moment and flashes it back at you. Five seconds of shame, then gone. Nothing saved, nothing shared.

🔥

Streak & Best Ever

Current streak since your last bite, plus the all-time record you're trying to beat. Watch the timer grow — or reset, loudly.

🎯

Today's Score

A 0–100 score every day, normalized against how long the camera was watching. Excellent, Good, Needs Work, or Rough Day.

🧠

Smart Detection

Finger curl analysis, depth filtering, and hysteresis keep false positives low. It knows the difference between biting, eating, and a chin rest.

🤫

Mute Mode

Eating lunch? One click to mute for 15 minutes, 1 hour, or until tomorrow. No false alarms.

🔊

Sound Library

Pick from six alert sounds — Funk, Pop, Tink, Sosumi, Ping, Glass. Preview each, tune the volume, and set the cooldown (1–60 seconds).

👁

Live Preview

Open the Preview tab to see exactly what the AI sees — face box, fingertips, distance-to-mouth, real-time FPS. Tune with your own eyes.

📷

Any Camera

Built-in FaceTime, Continuity Camera from your iPhone, or any external webcam. Pick whichever has the best view of your hands.

🚀

Set & Forget

Launches at login automatically. Pauses when your display sleeps. Runs silently from the menu bar, all day.

Lives in Your Menu Bar

Nail Snitch menu bar popover showing a 3:23 Current Streak, Today's Score of 100 (Excellent), 2 Bites Today, 90-second Best Streak, and a Mute Alerts button

Current Streak, Today's Score, Bites Today, Best Streak Ever, and one-click mute — all in a 320px menu bar popover.

Privacy First

Your Webcam Stays Yours

All detection runs locally on your Mac using Apple Vision. Snap Alert flashes the caught frame on your own screen for five seconds and then tosses it — nothing is written to disk, nothing ever leaves your Mac. No internet required.

100%Offline
0Images Stored
LocalAI Processing

Questions

No. Nail Snitch uses finger curl detection to distinguish biting (curled fingers near mouth) from eating or drinking (open hand, utensils). Plus you can mute it with one click for 15 minutes, 1 hour, or until tomorrow.
Nail Snitch processes at 15 frames per second using Apple's GPU-accelerated Vision framework. CPU usage stays under 5% when idle. It's designed to run all day without you noticing.
Never. Each frame is processed in memory and discarded. When Snap Alert fires, the caught still is shown on your screen for five seconds and then tossed — nothing is saved to disk and nothing ever leaves your Mac. The app runs sandboxed with camera access only — no network, no file system reach beyond its own settings.
Yes. Snap Alert is a toggle in Settings → Alerts. Keep just the audio beep if you'd rather skip the visual. Everything still happens on-device either way.
Any Mac with a built-in or connected webcam running macOS 14 (Sonoma) or later. Works with Apple Silicon and Intel Macs.
Yes. Nail Snitch is sold through the Mac App Store, so Apple's standard refund policy applies. You can request a refund within 14 days of purchase through Apple's Report a Problem page.
One-Time Purchase
$4.99
On the Mac App Store. No subscription.
  • All features included
  • Free updates
  • 100% offline — no account needed
  • Privacy-first, no data collection
  • macOS 14+ (Sonoma and later)
Download on the Mac App Store