# Costan vs Lucy Diary

The clearest difference is in-app purchases: Costan at none against Lucy Diary's 3. Costan also leads on iOS requirement (15.6 vs 17.0). Lucy Diary's advantage is update cadence (weekly vs every 6 weeks). On price, ads and device support there is nothing between them.

Both are free to download. Lucy Diary sells 3 in-app purchases, starting at $1.99 per month. Costan asks for nothing beyond the download.

Costan ships an update every 6 weeks, Lucy Diary weekly. The most recent releases landed on October 24, 2026 and October 18, 2026 respectively.

## The numbers

| Metric | Costan | Lucy Diary |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/lucy-diary-private-journal/id6769486832/reviews)** |
| Number of ratings | — | **1** |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 6 weeks | **Weekly** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 7 MB | 72 MB |
| Requires iOS | **15.6** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Shinichi Aokawa](https://appshunter.io/developer/502862033) | [Tahj Elliott](https://appshunter.io/developer/1896662619) |

## What reviewers say

### Costan

[App page](https://appshunter.io/ios/app/costan/id843202309)

Learn everyday greetings in 14 languages to connect with people worldwide. This app promotes a peaceful, borderless world through simple, friendly communication.

**Highlights:** Learn greetings in 14 languages, Promotes cross-cultural communication, Focuses on everyday phrases, Aims for a peaceful world, Simple and friendly interface

**Features:** Vision Pro support

**In-app purchases:** none


### Lucy Diary

[App page](https://appshunter.io/ios/app/lucy-diary-private-journal/id6769486832)

A private and cozy digital journal for daily thoughts, dreams, and memories. Offers a clean writing space with optional premium features for enhanced customization and photo attachments.

**Highlights:** Daily diary entries, Distraction-free writing space, Privacy-focused experience, Customization and cozy themes, Photo attachments, Premium diary layouts

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Diary+ Monthly | $1.99 | per month |
| Diary+ Yearly | $7.99 | per year |
| Diary+ Lifetime | $11.99 | one-time |


## Frequently asked questions

### Is Costan free?

Costan is free to download, with no in-app purchases.

### Is Lucy Diary free?

Lucy Diary is free to download, with in-app purchases available.

### Do Costan or Lucy Diary have ads?

Neither Costan nor Lucy Diary shows ads.

### Which is updated more often, Costan or Lucy Diary?

Costan ships an update every 6 weeks, and Lucy Diary weekly. Most recently, Costan was updated on October 24, 2026 and Lucy Diary on October 18, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*