Comparison

AtomicClock vs Radio Wave Sync

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

Radio Wave Sync

This app helps synchronize radio-controlled watches by simulating time signal waves. It supports various international time signal standards and offers a 'Beast Mode' for faster synchronization. Simply place your watch near your device's speaker and start the process.

Highlights
  • Simulates international time wave signals
  • Supports China, USA, Japan, Germany, and UK signals
  • Unique 'Beast Mode' for faster sync
  • Manual wave receiving mode calibration
  • Adjustable volume for optimal signal
Features
Read full description

I have a Casio G-Series radio watch, but it is always unable to receive radio waves from time signal station, so I started to write an application to solve this problem. After some research, I finally wrote this application, which can perfectly simulate the timing signal and happily calibrate the time. Usage method: 1. Adjust the volume of iPhone / iPad to the maximum. 2. Switch the radio controlled watch / clock to manual wave receiving mode. 3. Click the "start" button. 4. Place the watch / clock near the iPhone / iPad speakers. 5. The synchronization process generally takes 3-10 minutes, please wait patiently. Matters needing attention: 1. Please try to use the software in a quiet environment to avoid signal interference. 2. The volume of the mobile phone must be adjusted to the maximum. It's too small and the effect is not good. Characteristic: 1. Supports simulation of all types of Time Wave Signal: * China BPC * USA WWVB * Japan JJY40 / JJY60 * Germany DCF77 * British MSF 2. The unique "Beast Mode" provides higher frequency simulation signals and faster sync. Contact information: Please contact me if you have any use questions *QQ: 3364918353 *Email: 3364918353@qq.com

Screenshots

AtomicClock4 screens
Radio Wave Sync3 screens

Verdict

The call

The clearest difference is review sentiment: AtomicClock at 84% against Radio Wave Sync's 61%. AtomicClock also leads on rating (4.8 vs 4.5) and update cadence (every 3 weeks vs every 2 months). Radio Wave Sync's advantage is iOS requirement (13.0 vs 15.0). On price, ads, in-app purchases and monetization model 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 and Radio Wave Sync sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

AtomicClock holds the better App Store score, 4.8 against 4.5. That said, the two scores are not equally well evidenced: AtomicClock has 5.5K ratings behind it against 1K, so its average is the more settled of the two. Written reviews point the same way: 84% of AtomicClock's written reviews are positive against 61% of Radio Wave Sync's.

UpkeepUpdate frequency

AtomicClock ships an update every 3 weeks, Radio Wave Sync every 2 months. The most recent releases landed on October 17, 2026 and October 18, 2026 respectively.

Scorecard5 real differences · 5 level
AtomicClock versus Radio Wave Sync: the parameters behind the verdict, then further details
ParameterAtomicClockRadio Wave Sync
PriceFreeFree
Rating4.8 (5.5K ratings) — better4.5 (1K ratings)
Positive reviews84.2% of reviews — better61.5% of reviews
Number of ratings5.5K — better1K
Update frequencyEvery 3 weeks — betterEvery 2 months
AdsYesYes
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.013.0 — better
Further details — not scored
Size17 MB15 MB
Age rating4+4+
DeveloperTimo Partl宁 金

Customer experience

AtomicClock

All ratings5,539 ratings
Positive96.5%
Neutral1.8%
Negative1.8%
Written reviews241 reviews
Positive84.2%
Neutral3.3%
Negative12.4%

Radio Wave Sync

All ratings1,049 ratings
Positive87.4%
Neutral2.1%
Negative10.5%
Written reviews322 reviews
Positive61.5%
Neutral2.8%
Negative35.7%

User reviews

AtomicClock

From 5.5K App Store ratings

What we love

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

Room to improve

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

Radio Wave Sync

From 1K App Store ratings

What we love

  • 🚀 Works as intended
  • 👍 Easy to use
  • 💡 Innovative solution
  • 🔒 Reliable sync
  • ⏱️ Fast sync time

Room to improve

  • 🐛 Inconsistent performance
  • 💰 Paid version required
  • 🔇 Audio issues
  • 🤖 Ads in paid version
  • 🔁 One-time use only

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

Radio Wave Sync

Reported bugs

3 issues
  • No sound output
  • Sync failure after initial success
  • Incompatibility with certain watch models

Requested features

3 requests
  • Time zone offset option
  • Compatibility with newer devices
  • Improved reliability and consistency

In-app purchases

1 purchases

AtomicClock

One-time1
  • Lifetime Pro Version$6.99
1 purchases

Radio Wave Sync

One-time1
  • Pro Editon$1.99

Questions

Is AtomicClock free?
AtomicClock is free to download, with in-app purchases available.
Is Radio Wave Sync free?
Radio Wave Sync is free to download, with in-app purchases available.
Which has better reviews, AtomicClock or Radio Wave Sync?
AtomicClock is rated higher. AtomicClock averages 4.8 out of 5 from 5.5K ratings, while Radio Wave Sync averages 4.5 from 1K ratings.
Do AtomicClock or Radio Wave Sync have ads?
Both AtomicClock and Radio Wave Sync show ads.
Which is updated more often, AtomicClock or Radio Wave Sync?
AtomicClock ships an update every 3 weeks, and Radio Wave Sync every 2 months. Most recently, AtomicClock was updated on October 17, 2026 and Radio Wave Sync on October 18, 2026.

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