Comparison

The 21 Days Challenge vs Kapper

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

Head to head
About

The 21 Days Challenge

Build lasting habits and transform your life over 21 days with guided challenges. Track your progress, journal your thoughts, and customize your avatar with earned points. Discover new routines for health, productivity, and happiness.

Highlights
  • 21-day habit challenges
  • Habit tracking
  • Avatar customization
  • Daily journaling
  • Mood tracking
  • Community feed
  • Positive affirmations
Features
Read full description

Create your ideal life with life changing habits. It is estimated that it takes people 21 days to form a new habit. So it’s a perfect amount of time to change or introduce something new in your life. Choose the best challenge for you and do it for 21 days and you’re going to see how the habit becomes part of your lifestyle day by day. Starting a healthy lifestyle, taking a break away from the internet, practicing gratitude, trying to be more productive, simple practices to find happiness and calm in your life, how to study effectively for all the students, ways to spread kindness and positivity, tips for fixing your sleeping schedule and daily positive affirmations are some of the challenges that you can find in the app. Once you complete your daily task, you can mark as completed and collect the points (to customize your avatar). This way, you can use this app like a habit tracker. In the gratitude challenge, you can write your thoughts and share them in the feed (you can leave anonymously too). Here you're going to see all the community answers and you can also give it a like on your favorite ones. Complete tasks on your profile and do daily challenges to collect points so you can buy items for your own avatar like different hairstyles, eyes and mouth shapes and clothes. Create a healthier and happier mind with journaling. With this app you can daily journal and choose your daily mood. Then you can track your mood in the calendar and see all your previous records. You also a have a selection of positive wallpapers for your phone. Enable notifications and choose the time to be notified to remind you to do the challenge every day. Don’t forget to take care of your body and mind. It's the only place you have to live. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

Kapper

Features
Read full description

Kapper is the fastest way to book your next haircut. Find your barbershop, see real availability, and book in seconds — no phone calls, no waiting for a reply, no double-booked slots. BOOK IN SECONDS • See each shop's services, prices, and real-time availability • Pick your barber, pick your time, confirm — that's it • Instant confirmation with reminders so you never miss a cut YOUR SHOPS, YOUR BARBERS • Save your favorite barbershops • See each barber's portfolio before you choose • Book with the same barber every time STAY ON TOP OF IT • All your upcoming and past appointments in one place • Reschedule or cancel without an awkward phone call • Add appointments to your calendar • Get notified when it's almost time Available in English, Spanish, and French. Sign in with Apple, Google, or email — and get back to looking sharp.

Screenshots

The 21 Days Challenge4 screens
Kapper4 screens

Verdict

The call

The clearest difference is in-app purchases: Kapper at none against The 21 Days Challenge's 2. Kapper also leads on ads (none vs shown). On price, update cadence, device support and iOS requirement 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. The 21 Days Challenge sells 2 in-app purchases, starting at $2.99 per month. Kapper asks for nothing beyond the download.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly monthly. The most recent releases landed on October 26, 2026 and October 25, 2026 respectively.

Scorecard2 real differences · 8 level
The 21 Days Challenge versus Kapper: the parameters behind the verdict, then further details
ParameterThe 21 Days ChallengeKapper
PriceFreeFree
Rating4.7 (568 ratings) — better—
Positive reviews91.7% of reviews—
Number of ratings568 — better—
Update frequencyMonthlyMonthly
AdsYesNo — better
In-app purchasesYesNo — better
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS15.015.0
Further details — not scored
Size127 MB58 MB
Age rating4+4+
DeveloperKati Pereiraanass el moussaoui

Bugs and requests

The 21 Days Challenge

Reported bugs

2 issues
  • Sharing created challenges does not work as expected
  • Challenges sometimes disappear from the app

Requested features

4 requests
  • Add a search function for community challenges
  • Allow users to save and revisit their own created challenges
  • Provide more customization options for the app and user profile
  • Introduce a widget for easier access to daily tasks

Kapper

Not enough reviews yet to summarise bugs or requests.

In-app purchases

2 purchases

The 21 Days Challenge

Subscriptions2
  • Remove ads month$2.991 Month
  • Remove Ads Year$24.991 Year
None

Kapper

No in-app purchases

Questions

Is The 21 Days Challenge free?
The 21 Days Challenge is free to download, with in-app purchases available.
Is Kapper free?
Kapper is free to download, with no in-app purchases.
Do The 21 Days Challenge or Kapper have ads?
The 21 Days Challenge shows ads; Kapper does not.
Which is updated more often, The 21 Days Challenge or Kapper?
The 21 Days Challenge ships an update monthly, and Kapper monthly. Most recently, The 21 Days Challenge was updated on October 26, 2026 and Kapper on October 25, 2026.

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