Grinn - Smile Reminder
Your Daily Smile Reminder
Free · In‑App Purchases · Designed for iPad. Not verified for macOS.
Science says 10 seconds of smiling can change your mood. Grinn makes it a daily habit — with AI that knows when you're really smiling. Your brain will thank you.
Smiling for 10 seconds triggers real endorphins in your brain. Not metaphorically — a 2022 study across 19 countries with 3,878 participants confirmed it. Grinn turns that science into the simplest wellness habit you'll ever try.
No journaling. No 10-minute meditations. Just 10 seconds and your face.
HOW IT WORKS
Tap the button. A gentle countdown begins. Breathe in, hold, breathe out — the built-in breathing guide keeps you grounded. If you turn on smile detection, the timer only counts while you're genuinely smiling. That's it. One session, once a day, and your brain does the rest.
WHAT THE SCIENCE SAYS
This isn't wishful thinking. Grinn is built on 20+ peer-reviewed studies from journals like Nature Human Behaviour and Psychological Bulletin:
- 10 seconds of intentional smiling activates the facial feedback loop, releasing endorphins and serotonin
- Smiling reduces cortisol (your stress hormone) by up to 25%
- A mega-study across 19 countries confirmed the effect is real and replicable
- Even a "forced" smile triggers the same neurological pathways as a genuine one
Grinn includes a full Science section with every study cited — because you deserve to know why this works, not just that it does.
FEATURES
- Guided smile sessions with a breathing guide and haptic feedback
- AI smile detection — the timer pauses if you stop smiling and resumes when you start again
- Streak tracking with milestones at 3, 7, 14, 21, 30, 50, 75, 100, and 365 days
- Daily quotes to keep you inspired
- Smart reminders that nudge you at the right moments
- Dark mode, accessibility support, and privacy by design
GRINN PRO
Unlock the full experience:
- Unlimited daily sessions (free: 3 per day)
- Smile Journal — auto-captured selfies that build a visual timeline of your smiles, stored privately on your device
- Custom timer duration (10-30 seconds)
- Unlimited reminders with custom notification messages
- Full quote library
BUILT WITH CARE
Your photos never leave your device. Camera access is optional. Animations respect your accessibility settings. We built Grinn to be honest — the app even acknowledges that the research shows real but modest effects. No magic promises, just a small daily habit backed by good science.
Feeling better doesn't have to be complicated. It can start with 10 seconds and a smile.
SUBSCRIPTION INFORMATION
Grinn Pro is an optional auto-renewable subscription that unlocks unlimited sessions, Smile Journal, custom timer, unlimited reminders, and the full quote library.
- Monthly: $0.99/month
- Annual: $9.99/year
- Lifetime: $27.99 (one-time purchase)
Payment will be charged to your Apple ID account at confirmation of purchase. Monthly and Annual subscriptions automatically renew unless canceled at least 24 hours before the end of the current period. You can manage or cancel your subscriptions in your device's Settings > Apple ID > Subscriptions.
Terms of Use: https://www.grinnapp.com/terms
Privacy Policy: https://www.grinnapp.com/privacy
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
The developer, Gonzalo Perez Rojas, 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 Linked to You
The following data may be collected but it is not linked to your identity:
- Purchases
- Identifiers
- Usage Data
- Diagnostics
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Gonzalo Perez Rojas
- Size
- 81.3 MB
- Category
- Health & Fitness
- Compatibility
Requires iOS 16.0 or later.
- iPhone
Requires iOS 16.0 or later. - iPad
Requires iPadOS 16.0 or later. - Mac
Requires macOS 13.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
9+
- 9+
- Contains
Health or Wellness Topics
- In-App Purchases
Yes
- Yearly $9.99
- Lifetime $27.99
- Grinn Pro Monthly $0.99
- Copyright
- © 2026, 0xG Labs
