21DaysOfChange vs Dayletter
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
Dayletter
This private journal app creates dated Markdown entries in your chosen Obsidian folder. It safely merges new content with existing files and allows categorization by type, such as investing or exercise. Capture moments, manage tasks with due dates, and access your journal locally without accounts or ads.
- Obsidian-compatible Markdown and tags
- Dated Markdown entry creation
- Safe merging with existing files
- Categorization by type (investing, exercise, etc.)
- Task management with start and due dates
- Local drafts and iCloud Drive support
- No accounts, ads, or data uploads
Read full descriptionHide full description
Dayletter is a private journal made for capturing the moment. Choose your Obsidian journal folder and Dayletter writes dated Markdown entries into it. If a daily file already exists, Dayletter merges its own section safely and leaves your existing writing intact. Capture moments under a type such as investing, exercise, or reading—or keep Tasks with start and due dates. - Obsidian-compatible Markdown and tags - Read by day or category, plus a task list - Consecutive notes under one type are naturally grouped - Use any local or iCloud Drive folder - Local drafts are kept when a file is downloading, syncing, or conflicted - No accounts, no ads, and no data uploads Send this moment to your future self.
Screenshots
Verdict
The clearest difference is in-app purchases: Dayletter at none against 21DaysOfChange's 4. Dayletter also leads on update cadence (every 3 days vs every 9 months). On price, ads, 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
Both are free to download. 21DaysOfChange sells 4 in-app purchases, starting at $4.99 per month. Dayletter asks for nothing beyond the download.
21DaysOfChange ships an update every 9 months, Dayletter every 3 days. The most recent releases landed on October 21, 2026 and October 12, 2026 respectively.
| Parameter | 21DaysOfChange | Dayletter |
|---|---|---|
| Price | Free | Free |
| Rating | — | 5.0 (1 ratings) — better |
| Number of ratings | — | 1 — better |
| Update frequency | Every 9 months | Every 3 days — better |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | — | Free |
| Devices | iPhone, iPad — better | iPhone |
| Requires iOS | 16.4 — better | 17.0 |
| Further details — not scored | ||
| Size | 59 MB | 4 MB |
| Age rating | 4+ | 4+ |
| Developer | Hong Son Vu | 磊 徐 |
In-app purchases
21DaysOfChange
- 21DaysOfChange Monthly Premium$4.991 Month
- 21DaysOfChange Monthly Business$12.991 Month
- 21DaysOfChange Yearly Premium$34.991 Year
Show 1 moreShow fewer
- 21DaysOfChange Yearly Business$89.991 Year
Dayletter
No in-app purchases









