Pick your challenge
Choose from curated 21-day challenges or design your own — health, learning, focus, mindfulness, anything that matters to you.
Built for real, lasting change
Build habits that stick — 21 days at a time.
Pick a goal, commit for 21 days, and check in daily. Simple habit tracking with streaks, journals, and gentle reminders — across health, learning, productivity, and more.
Private by default
No card needed
How it works
Three simple steps. Real, lasting change.
No clutter, no gimmicks. Just the gentlest possible path from intention to habit.
Check in daily
A simple tap to log your day. Add a note, mood, or reflection. Smart reminders nudge you at the right time, never naggy.
Watch the streak grow
See your progress build over 21 days. Earn badges, unlock milestones, and turn intention into identity — one day at a time.
Features
Everything you need to stick with it
A complete habit-building system in your pocket — minus the noise.
Multiple challenges
Run several habits at once — drink water, read, walk, anything. Track them all on a single home screen.
Streaks & milestones
Watch your streak climb, hit milestones like Day 7 and Day 14, and unlock badges as you grow.
Daily journal
Reflect with quick notes or longer entries. Track mood alongside habits to spot what's really working.
Insightful stats
See completion rates, mood patterns, and lifetime progress — beautiful charts that actually mean something.
Smart reminders
Gentle alarms and notifications at the times that fit your day. Custom per-challenge schedules.
Private by default
Your data lives on your device by default. Optional sync with end-to-end privacy. Nothing sold, ever.
What people work on
Built for every kind of growth
Pick the area that matters to you — start small, finish strong.
Learning
Read, study, grow daily
Productivity
Focus, output, discipline
Health
Water, sleep, movement
Personal Goals
Your own milestones
Daily Habits
Consistency over perfection
Creativity
Create something every day
Loved by habit-builders
What Our Clients Say
Thousands of people are building habits that stick. Here's what a few of them say.
"Clean and Simple Design. I really like that they give only one goal setting at a time. Focus on one goal only and do it and then take another goal. That help improve the focus"
"i just love this app.. no add no drama..simple, easy & helpful"
"this app helps me to keep track of my workouts I will be using this app a lot"
From the blog
Ideas on building habits that stick
Short, honest reads on consistency, motivation, and the thinking behind the app.
From the team
Why we built 21 Day Challenge
Good intentions are easy — showing up every day is hard. Here's the problem we set out to solve, and the gentle, focused system behind it.
FAQ
Questions we get asked a lot
Why 21 days?
21 days is a popular and approachable window for building consistency.
It's long enough to feel real progress, short enough to stay focused.
Once a 21-day cycle ends, you can roll into a new one — or stack
another habit on top.
Do I need to create an account?
Nope. The app works fully offline with no account. If you want your
challenges, history, and notes synced across devices, you can add
an email — but it's completely optional.
Is the app really free?
Yes. The app is free to use — no charge, no card. Just download
it, pick a goal, and start your first 21-day challenge.
Is my data private?
Yes. Your data stays on your device unless you opt into cloud sync.
We never sell or share your data. You can delete your account and
all associated data at any time — see our
Privacy Policy.
Can I track more than one habit at a time?
Yes. You can track multiple active challenges at once, so you
can stack habits without feeling overwhelmed.
How do I delete my account?
You can request deletion in-app from Profile → Settings → Delete
Account, or use the form on our
account deletion page.
Your data is removed within 30 days.
Start your first 21 days today.
Download the app, pick a goal, and let's build something that lasts. Free to start, no card needed.