# ATclock vs Millisecond Clock

The clearest difference is in-app purchases: ATclock at none against Millisecond Clock's 3. ATclock also leads on ads (none vs shown) and update cadence (weekly vs every 6 months). On price and device support there is nothing between them.

Both are free to download. Millisecond Clock sells 3 one-off in-app purchases. ATclock asks for nothing beyond the download.

ATclock ships an update weekly, Millisecond Clock every 6 months. The most recent releases landed on September 20, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | ATclock | Millisecond Clock |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.7 (131 ratings)](https://appshunter.io/ios/app/millisecond-clock/id1526615560/reviews)** |
| Number of ratings | — | **131** |
| Positive reviews | — | 72.7% of reviews |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | **Weekly** | Every 6 months |
| Monetization | — | Free with in-app purchases |
| Size | 11 MB | 4 MB |
| Requires iOS | **9.0** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [ADSMART TECHNOLOGY LIMITED](https://appshunter.io/developer/1217365227) | [Chia-Chun Hsieh](https://appshunter.io/developer/908221958) |

## What reviewers say

### ATclock

[App page](https://appshunter.io/ios/app/atclock/id1456453238)

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

**In-app purchases:** none


### Millisecond Clock

[App page](https://appshunter.io/ios/app/millisecond-clock/id1526615560)

This app displays the most accurate time available, down to the millisecond. It's useful for measuring network delays or video streaming lag by comparing displayed time differences.

**Highlights:** Millisecond precision time display, Accurate timekeeping for iPhone and iPad, Network delay measurement, Video streaming lag analysis, Free to download

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $0.99 | one-time |
| Special Offer Package | $2.99 | one-time |
| Unlock Themes | $3.99 | one-time |


## Frequently asked questions

### Is ATclock free?

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

### Is Millisecond Clock free?

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

### Do ATclock or Millisecond Clock have ads?

Millisecond Clock shows ads; ATclock does not.

### Which is updated more often, ATclock or Millisecond Clock?

ATclock ships an update weekly, and Millisecond Clock every 6 months. Most recently, ATclock was updated on September 20, 2026 and Millisecond Clock on October 14, 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.*