# Atomic Clock PRO vs Cool Ukiyo

The clearest difference is update cadence: Cool Ukiyo at monthly against Atomic Clock PRO's every 3 months. Cool Ukiyo also leads on iOS requirement (12.0 vs 15.6). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Atomic Clock PRO sells 2 in-app purchases, starting at $1.99 per month and Cool Ukiyo sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Atomic Clock PRO ships an update every 3 months, Cool Ukiyo monthly. The most recent releases landed on October 2, 2026 and September 9, 2026 respectively.

## The numbers

| Metric | Atomic Clock PRO | Cool Ukiyo |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (10K ratings)](https://appshunter.io/ios/app/atomic-clock-pro/id899090224/reviews)** | — |
| Number of ratings | **10K** | — |
| Positive reviews | 72.9% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | Yes | Yes |
| Update frequency | Every 3 months | **Monthly** |
| Monetization | Free with in-app purchases | — |
| Size | 6 MB | 53 MB |
| Requires iOS | 15.6 | **12.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Brachmann Online Marketing GmbH & Co. KG](https://appshunter.io/developer/682848918) | [Mihoko Araki](https://appshunter.io/developer/1476136915) |

## What reviewers say

### Atomic Clock PRO

[App page](https://appshunter.io/ios/app/atomic-clock-pro/id899090224)

Get the most accurate time from an official atomic clock server. This app automatically detects your time zone and allows custom backgrounds. Easily switch between digital and analog clock displays with a swipe.

**Highlights:** Exact time from atomic clock, Automatic time zone recognition, Customizable background images, Digital and analog clock modes, Optional sound alerts, Color customization

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium | $1.99 | per month |
| Remove Ads | $5.99 | one-time |

**What reviewers like**

- ⭐ Accurate time display
- 📟 Useful for timing events
- 🕰️ Helpful for setting other clocks
- 🔍 Large, easy-to-read clock face

**What reviewers complain about**

- 💸 Subscription model for ad-free version
- 📢 Excessive advertisements
- 🔍 Small font for seconds display
- 🔀 Difficulty in displaying both analog and digital clocks simultaneously

**Reported bugs**

- Second hand occasionally runs in reverse
- Digital clock display cuts off on some devices
- Inconsistent behavior when switching between clock types

**Requested features**

- Customizable clock face options
- Ability to set widget on home screen
- Sync with system clock to automatically update time


### Cool Ukiyo

[App page](https://appshunter.io/ios/app/cool-ukiyo-e-clock/id6503263276)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Cool Ukiyo-e Clock with no ads | $3.99 | one-time |


## Frequently asked questions

### Is Atomic Clock PRO free?

Atomic Clock PRO is free to download, with in-app purchases available.

### Is Cool Ukiyo free?

Cool Ukiyo is free to download, with in-app purchases available.

### Do Atomic Clock PRO or Cool Ukiyo have ads?

Both Atomic Clock PRO and Cool Ukiyo show ads.

### Which is updated more often, Atomic Clock PRO or Cool Ukiyo?

Atomic Clock PRO ships an update every 3 months, and Cool Ukiyo monthly. Most recently, Atomic Clock PRO was updated on October 2, 2026 and Cool Ukiyo on September 9, 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.*