# MERIDEN311 vs Atomic Clock

The clearest difference is in-app purchases: MERIDEN311 at none against Atomic Clock's 2. MERIDEN311 also leads on iOS requirement (15.1 vs 17.6). Atomic Clock's advantage is update cadence (every 6 weeks vs every 20 months). On price, ads and device support there is nothing between them.

Both are free to download. Atomic Clock sells 2 in-app purchases, starting at $5.99 per month. MERIDEN311 asks for nothing beyond the download.

MERIDEN311 ships an update every 20 months, Atomic Clock every 6 weeks. The most recent releases landed on September 8, 2026 and September 18, 2026 respectively.

## The numbers

| Metric | MERIDEN311 | Atomic Clock |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.8 (4 ratings)](https://appshunter.io/ios/app/atomic-clock-precision-time/id6760377377/reviews)** |
| Number of ratings | — | **4** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 20 months | **Every 6 weeks** |
| Monetization | — | Free with in-app purchases |
| Size | 44 MB | 9 MB |
| Requires iOS | **15.1** | 17.6 |
| Devices | **iPhone, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [City of Meriden](https://appshunter.io/developer/1692659130) | [家宝 戴](https://appshunter.io/developer/1826395838) |

## What reviewers say

### MERIDEN311

[App page](https://appshunter.io/ios/app/meriden311/id6450278881)

**In-app purchases:** none


### Atomic Clock

[App page](https://appshunter.io/ios/app/atomic-clock-precision-time/id6760377377)

This utility provides highly accurate time synchronization using NTP, displaying precise time with millisecond detail. It allows comparison with network time, shows sync offset and latency, and offers various clock styles with customization options. It's designed for users needing a reliable, precise reference clock.

**Highlights:** NTP-based time synchronization, Millisecond time detail, Local time and UTC display, Device offset and network latency indicators, Automatic sync, Multiple clock styles, Customizable colors and night mode

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| AtomicClock Pro Monthly | $5.99 | per month |
| AtomicClock Pro Monthly | $19.99 | per year |


## Frequently asked questions

### Is MERIDEN311 free?

MERIDEN311 is free to download, with no in-app purchases.

### Is Atomic Clock free?

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

### Do MERIDEN311 or Atomic Clock have ads?

Neither MERIDEN311 nor Atomic Clock shows ads.

### Which is updated more often, MERIDEN311 or Atomic Clock?

MERIDEN311 ships an update every 20 months, and Atomic Clock every 6 weeks. Most recently, MERIDEN311 was updated on September 8, 2026 and Atomic Clock on September 18, 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.*