# AtomicClock vs ClockSync Pro

The clearest difference is in-app purchases: ClockSync Pro at none against AtomicClock's 1. ClockSync Pro also leads on ads (none vs shown) and iOS requirement (13.0 vs 17.4). On price and device support there is nothing between them.

Both are free to download. AtomicClock sells 1 one-off in-app purchase. ClockSync Pro asks for nothing beyond the download.

## The numbers

| Metric | AtomicClock | ClockSync Pro |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (5.6K ratings)](https://appshunter.io/ios/app/atomicclock-ntp-time/id1402993049/reviews)** | — |
| Number of ratings | **5.6K** | — |
| Positive reviews | 84.3% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Monthly | — |
| Monetization | Free with in-app purchases | — |
| Size | 17 MB | 1 MB |
| Requires iOS | 17.4 | **13.0** |
| Devices | iPhone, iPad | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Timo Partl](https://appshunter.io/developer/1387413672) | [春演 余](https://appshunter.io/developer/1886758083) |

## What reviewers say

### AtomicClock

[App page](https://appshunter.io/ios/app/atomicclock-ntp-time/id1402993049)

This app displays the exact current time synchronized with NTP servers, offering a customizable clock view for precise time checks. It's ideal for setting watches, verifying timestamps, or comparing local and network time.

**Highlights:** Precise time from NTP servers, Customizable clock faces, Select or add time servers, Local and UTC views, 12/24 hour modes, Customizable time format, Acoustic ticking

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Lifetime Pro Version | $6.99 | one-time |

**What reviewers like**

- 🚀 Accurate time
- 👍 Highly customizable
- 🚀 Precise to the second
- 👍 Easy to use
- 👍 Helpful for setting watches

**What reviewers complain about**

- 🐛 Server connection issues
- 🔍 Limited time zone options
- 💰 Ads diminish clock view
- 🔍 Lacks some advanced features
- 🔍 Redundant for some users

**Reported bugs**

- Crashes on certain iOS versions
- Occasional freezing of hands
- Countdown timer sound not working

**Requested features**

- Add GMT/dual time display
- Implement widget support
- Add different second hand sounds
- Allow setting background color to match watch
- Include alarm/timer functionality


### ClockSync Pro

[App page](https://appshunter.io/ios/app/clocksync-pro/id6814334818)

**In-app purchases:** none


## Frequently asked questions

### Is AtomicClock free?

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

### Is ClockSync Pro free?

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

### Do AtomicClock or ClockSync Pro have ads?

AtomicClock shows ads; ClockSync Pro does not.

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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.*