Comparison

AtomicClock vs Atomic Clock

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

AtomicClock

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
Read full description

Check precise NTP reference time at a glance. AtomicClock helps you set watches, wall clocks, cameras, and other devices, compare local time with UTC, and follow moments when every second matters. Clear analog and digital time AtomicClock displays current time from NTP servers that reference atomic clocks. Choose a predefined server or add your own, then view local or UTC time in a clean analog or digital clock. Customize your reference clock • Switch between 12-hour and 24-hour time • Customize the time format • Choose from multiple clock faces and hands • Use a smooth, fluid second hand • Add acoustic ticking or the Greenwich Time Signal • Tap the screen to hide information and controls, freeze the display, or mute ticking Details for precise time checks View technical NTP information, including round-trip time and server stratum. Whether you are checking a timestamp, preparing a camera, aligning a wall clock, or setting a watch by hand, the seconds remain clear and easy to follow. AtomicClock is free to use. AtomicClock Pro is available as a one-time purchase with no subscription. It unlocks your preferred clock face, hands, and font, removes ads, and includes upcoming Pro features. AtomicClock displays NTP reference time for comparison and does not change your device’s system time. Results can vary with the selected server, network conditions, and device behavior.

About

Atomic Clock

Features
Read full description

Always know the exact time with Atomic Clock – Precise Time. Our app synchronizes with official atomic time servers to deliver ultra-accurate time down to the millisecond. Whether you’re coordinating across time zones, managing scientific experiments, or simply want the most reliable clock, this app provides unmatched precision. Features: - Real-time synchronization with global atomic clock servers - 24-hour and 12-hour display options - Beautiful, minimal clock face with dark mode - Works online and offline with last known atomic time - Perfect for professionals, travelers, pilots, scientists, and anyone who values absolute accuracy. An atomic clock is a timekeeping device that measures time based on the vibrations or transitions of atoms—usually cesium or rubidium. Unlike mechanical or quartz clocks, which rely on moving parts or crystals, atomic clocks use the natural oscillations of atoms as their frequency standard. This makes them the most accurate clocks ever developed, capable of maintaining time to within a few billionths of a second per day. Atomic clocks are essential for applications where extreme precision is required, such as GPS navigation, telecommunications, space exploration, scientific experiments, and synchronizing global networks.

Screenshots

AtomicClock4 screens
Atomic Clock3 screens

Verdict

The call

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

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

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

Scorecard2 real differences · 8 level
AtomicClock versus Atomic Clock: the parameters behind the verdict, then further details
ParameterAtomicClockAtomic Clock
PriceFreeFree
Rating4.8 (5.5K ratings) — better—
Positive reviews84.5% of reviews—
Number of ratings5.5K — better—
Update frequencyEvery 3 weeks—
AdsYesNo — better
In-app purchasesYesNo — better
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS15.0 — better15.1
Further details — not scored
Size17 MB29 MB
Age rating4+4+
DeveloperTimo PartlSTAN I. C. ALEXANDRU PERSOANA FIZICA AUTORIZATA

Bugs and requests

AtomicClock

Reported bugs

3 issues
  • Crashes on certain iOS versions
  • Occasional freezing of hands
  • Countdown timer sound not working

Requested features

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

Atomic Clock

Not enough reviews yet to summarise bugs or requests.

In-app purchases

1 purchases

AtomicClock

One-time1
  • Lifetime Pro Version$6.99
None

Atomic Clock

No in-app purchases

Questions

Is AtomicClock free?
AtomicClock is free to download, with in-app purchases available.
Is Atomic Clock free?
Atomic Clock is free to download, with no in-app purchases.
Do AtomicClock or Atomic Clock have ads?
AtomicClock shows ads; Atomic Clock does not.

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