10 Seconds to a Better Mood.
Backed by Science.
Your daily nudge to pause, breathe, and smile. Just 10 seconds can shift your whole mood.
Everything you need to build the habit
Grinn makes smiling a daily practice — not a chore. Simple tools, real science, zero friction.
AI Smile Detection
Your camera confirms your smile with real-time AI feedback. No photos saved — ever.
10-Second Sessions
Too short to skip, long enough to shift your mood. Fits between anything.
Guided Breathing
A calming 4-1-4 breathing guide synced to your smile session. Inhale calm, exhale stress.
Streak System
Build momentum with daily streaks. Hit milestones at 3, 7, 14, 30, and 100 days.
Daily Quotes
A fresh, curated quote each day to spark your smile. Unlock the full library with Pro.
Gentle Reminders
Customizable nudges throughout the day. Morning, afternoon, or evening — you choose.
How it works
Three steps. Ten seconds. Zero excuses.
Open & Tap
Open the app and tap "Smile Now." That's it.
Smile for 10s
Follow the breathing guide while AI detects your smile in real-time.
Build Your Streak
Come back tomorrow. Unlock milestone badges and track your progress.
A 2022 mega-study across 19 countries with 3,878 participants confirmed: intentionally smiling can genuinely boost your happiness.
Coles et al., 2022 — Nature Human Behaviour
People are smiling more
Real stories from real smilers.
“I was skeptical, but this tiny habit genuinely shifted my mornings. 10 seconds is nothing — but it changes everything.”
“The breathing guide + smile combo is surprisingly calming. My stress levels have dropped noticeably since starting.”
“I'm on a 47-day streak and it's become my favorite micro-ritual. Simple, quick, and it actually works.”
Your smile is waiting.
Download Grinn and start your first 10-second smile session today. It's free, private, and takes less time than reading this sentence.
Based on the 2022 Many Smiles Collaboration — the largest-ever study on facial feedback, published in Nature Human Behaviour.