# Costan vs DDays

The clearest difference is update cadence: DDays at every 2 weeks against Costan's every 6 weeks. Costan's advantage is device support (3 vs 1) and iOS requirement (15.6 vs 17.0). On price, review sentiment, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Costan ships an update every 6 weeks, DDays every 2 weeks. The most recent releases landed on September 9, 2026 and June 5, 2026 respectively.

## The numbers

| Metric | Costan | DDays |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 100.0% of reviews | 100.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 6 weeks | **Every 2 weeks** |
| Monetization | Free | Free |
| Size | 7 MB | 5 MB |
| Requires iOS | **15.6** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Shinichi Aokawa](https://appshunter.io/developer/502862033) | [Lee Jaeho](https://appshunter.io/developer/1556252425) |

## 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


### DDays

[App page](https://appshunter.io/ios/app/ddays/id6469691671)

Track important upcoming events with timely notifications. View countdowns directly on your home screen and lock screen widgets.

**Highlights:** D-day tracking, Advance notifications, Home screen widget, Lock screen widget, Live activity display

**In-app purchases:** none


## Frequently asked questions

### Is Costan free?

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

### Is DDays free?

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

### Do Costan or DDays have ads?

Neither Costan nor DDays shows ads.

### Which is updated more often, Costan or DDays?

Costan ships an update every 6 weeks, and DDays every 2 weeks. Most recently, Costan was updated on September 9, 2026 and DDays on June 5, 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.*