# Atomic Clock PRO vs Chronometer

The clearest difference is review sentiment: Atomic Clock PRO at 73% against Chronometer's 0%. Atomic Clock PRO also leads on price (Free vs $2.99) and rating (4.7 vs 3.1). Chronometer's advantage is in-app purchases (none vs 2) and ads (none vs shown). On update cadence and device support there is nothing between them.

Atomic Clock PRO is free to download; Chronometer costs $2.99 up front. Atomic Clock PRO sells 2 in-app purchases, starting at $1.99 per month. Chronometer asks for nothing beyond the download.

Atomic Clock PRO holds the better App Store score, 4.7 against 3.1. That said, the two scores are not equally well evidenced: Atomic Clock PRO has 10K ratings behind it against 8, so its average is the more settled of the two. Written reviews point the same way: 73% of Atomic Clock PRO's written reviews are positive against 0% of Chronometer's.

Atomic Clock PRO ships an update every 3 months, Chronometer every 5 months. The most recent releases landed on October 13, 2026 and October 8, 2026 respectively.

## The numbers

| Metric | Atomic Clock PRO | Chronometer |
| --- | --- | --- |
| Price | **Free** | $2.99 |
| Rating | **[4.7 (10K ratings)](https://appshunter.io/ios/app/atomic-clock-pro/id899090224/reviews)** | [3.1 (8 ratings)](https://appshunter.io/ios/app/chronometer/id1562013733/reviews) |
| Number of ratings | **10K** | 8 |
| Positive reviews | **73.0% of reviews** | 0.0% of reviews |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | **Every 3 months** | Every 5 months |
| Monetization | **Free with in-app purchases** | Paid |
| Size | 6 MB | 3 MB |
| Requires iOS | **15.6** | 18.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Brachmann Online Marketing GmbH & Co. KG](https://appshunter.io/developer/682848918) | [Kilian Eisenegger](https://appshunter.io/developer/1333678887) |

## 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


### Chronometer

[App page](https://appshunter.io/ios/app/chronometer/id1562013733)

Easily track your watch's accuracy against atomic time. Simply set your watch to atomic time, take a photo of the dial within the app, and record the difference. Analyze daily deviations over 15 days to assess your watch's performance.

**Highlights:** Track daily watch accuracy, Compare against atomic time, Photo capture for time reading, Altitude recording, Save data in CSV format, Analyze 15-day data trends

**In-app purchases:** none


## Frequently asked questions

### Is Atomic Clock PRO free?

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

### Is Chronometer free?

Chronometer costs $2.99, with no in-app purchases.

### Which has better reviews, Atomic Clock PRO or Chronometer?

Atomic Clock PRO is rated higher. Atomic Clock PRO averages 4.7 out of 5 from 10K ratings, while Chronometer averages 3.1 from 8 ratings.

### Do Atomic Clock PRO or Chronometer have ads?

Atomic Clock PRO shows ads; Chronometer does not.

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

Atomic Clock PRO ships an update every 3 months, and Chronometer every 5 months. Most recently, Atomic Clock PRO was updated on October 13, 2026 and Chronometer on October 8, 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.*