Comparison

21DaysOfChange vs 21

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

21DaysOfChange

Features
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With our clear guidance and a bit of fun, we'll help you transform your habits into something you can be proud of. Imagine growing a tree - starting small, nurturing it daily, and watching it flourish. In just 21 days, you'll cultivate a new habit with tips and strategies that will last a lifetime. Join us on this transformative journey and take control of your lifestyle, one habit at a time. Terms Of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://www.21daysofchange.app/privacypolicy

About

21

Features
Read full description

Boost your happiness—backed by science Small actions can create big change. Happiness Challenge bundles five research-driven habits into one beautifully simple app and guides you through a 21-day journey to a happier, healthier you. The 5-Step Daily Formula 1. Gratitude Journal – Spend 2 minutes noting things you’re grateful for. 2. Meaningful Moment Journal – Reflect on one positive experience from the last 24 hours. 3. Thank-You Message – Strengthen relationships by sending a quick note of appreciation. 4. 15-Minute Cardio Burst – Elevate mood-boosting endorphins with movement you enjoy. 5. Mindful Meditation – Center yourself with a short meditation. Why you’ll love it * One-Tap Tracking - Toggle each habit as you complete it—watch your daily checklist glow. * 21-Day Streak Calendar - See at a glance which days you’ve hit all five tasks and keep your streak alive. * Journals that Spark Joy - Beautiful, distraction-free spaces for gratitude and meaningful-moment entries. * Memories That Last - Browse past journal pages anytime to relive uplifting thoughts and wins. * Gentle Reminders - Custom notifications help you stay on course without the guilt trip. * Private & Secure - Your reflections are stored safely on your device. Start your happiness challenge today Download Happiness Challenge, commit just a few minutes a day, and feel the difference. Your happier self is 21 days away—ready to begin?

Screenshots

21DaysOfChange4 screens
214 screens

Verdict

The call

The clearest difference is in-app purchases: 21 at none against 21DaysOfChange's 4. 21 also leads on update cadence (weekly vs every 9 months) and iOS requirement (12.0 vs 16.4). On price, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. 21DaysOfChange sells 4 in-app purchases, starting at $5.99 per month. 21 asks for nothing beyond the download.

UpkeepUpdate frequency

21DaysOfChange ships an update every 9 months, 21 weekly. The most recent releases landed on September 18, 2026 and September 9, 2026 respectively.

Scorecard3 real differences · 3 level
21DaysOfChange versus 21: the parameters behind the verdict, then further details
Parameter21DaysOfChange21
PriceFreeFree
Update frequencyEvery 9 monthsWeekly — better
AdsNoNo
In-app purchasesYesNo — better
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS16.412.0 — better
Further details — not scored
Size59 MB23 MB
Age rating4+4+
DeveloperHong Son VuBrogdon Co, LLC

In-app purchases

4 purchases

21DaysOfChange

Subscriptions4
  • 21DaysOfChange Monthly Premium$5.991 Month
  • 21DaysOfChange Monthly Business$17.991 Month
  • 21DaysOfChange Yearly Premium$71.991 Year
Show 1 more
  • 21DaysOfChange Yearly Business$214.991 Year
None

21

No in-app purchases

Questions

Is 21DaysOfChange free?
21DaysOfChange is free to download, with in-app purchases available.
Is 21 free?
21 is free to download, with no in-app purchases.
Do 21DaysOfChange or 21 have ads?
Neither 21DaysOfChange nor 21 shows ads.
Which is updated more often, 21DaysOfChange or 21?
21DaysOfChange ships an update every 9 months, and 21 weekly. Most recently, 21DaysOfChange was updated on September 18, 2026 and 21 on September 9, 2026.

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