21DaysOfChange vs 21
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
21DaysOfChange
Read full descriptionHide full description
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
21
Read full descriptionHide 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
Verdict
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
Both are free to download. 21DaysOfChange sells 4 in-app purchases, starting at $5.99 per month. 21 asks for nothing beyond the download.
21DaysOfChange ships an update every 9 months, 21 weekly. The most recent releases landed on September 18, 2026 and September 9, 2026 respectively.
| Parameter | 21DaysOfChange | 21 |
|---|---|---|
| Price | Free | Free |
| Update frequency | Every 9 months | Weekly — better |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 16.4 | 12.0 — better |
| Further details — not scored | ||
| Size | 59 MB | 23 MB |
| Age rating | 4+ | 4+ |
| Developer | Hong Son Vu | Brogdon Co, LLC |
In-app purchases
21DaysOfChange
- 21DaysOfChange Monthly Premium$5.991 Month
- 21DaysOfChange Monthly Business$17.991 Month
- 21DaysOfChange Yearly Premium$71.991 Year
Show 1 moreShow fewer
- 21DaysOfChange Yearly Business$214.991 Year
21
No in-app purchases









