Comparison

Atomic Clock PRO vs Atomic Sync

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

Head to head
About

Atomic Clock PRO

Get the most accurate time from an official atomic clock server. This app automatically detects your time zone and allows custom backgrounds. Easily switch between digital and analog clock displays with a swipe.

Highlights
  • Exact time from atomic clock
  • Automatic time zone recognition
  • Customizable background images
  • Digital and analog clock modes
  • Optional sound alerts
  • Color customization
Features
Read full description

Get accurate time on your iPhone and iPad by syncing with an official atomic clock time server. Download now for free! If you want exact time, a precise time reference, or an easy-to-read clock display, this app is designed for that. It automatically recognizes your time zone, lets you use one of your own photos as the background, and lets you switch between a digital display and a classic analog clock with a simple swipe. It is ideal as a personalized desk clock, a reliable travel companion, an everyday reference clock, or when you need exact time to set a mechanical watch accurately. Overview: - Accurate and precise time synced from an official atomic clock time server - Automatically recognizes your time zone and shows the current local time - Choose digital, analog, or combined analog and digital clock displays - Swipe to switch between clock displays - Resize the digital clock for a larger or smaller display - Includes time (hours, minutes, and seconds), date, and day of the week (optional) - Optional sound every second or every minute - Change clock and background colors - Use your own photos as background images - Choose atomic clock sync or your device's system clock - Option to keep the screen awake while the app is open - Works in portrait and landscape mode - For iPhone and iPad Helpful for: - A personalized desk clock at home or at work - Getting the correct local time while traveling - Setting a mechanical watch accurately - A clear reference clock when you want accurate, easy-to-read time PLEASE NOTE: You can switch between the analog and digital clock by swiping left or right across the clock. Disclaimer: Please note that whilst all reasonable care has been taken to make this application as accurate as possible we can not guarantee 100% accuracy. Standard Apple Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

Atomic Sync

Features
Read full description

Sync Your Radio-Controlled Watch in Minutes! Atomic Sync emulates official atomic time signals to synchronize your radio-controlled watch — no tower reception needed. Works with Casio G-Shock, Citizen, Lacrosse, Junghans, Braun and other atomic watches. SUPPORTED TIME SIGNALS: • WWVB (60 kHz) — United States • DCF77 (77.5 kHz) — Germany / Europe • JJY40 / JJY60 (40/60 kHz) — Japan • MSF (60 kHz) — United Kingdom • BPC (68.5 kHz) — China • RBU (66.66 kHz) — Russia HOW IT WORKS: 1. Select your region or time signal 2. Place your phone near your watch (see visual guide) 3. Tap Start and wait 1-10 minutes 4. Your watch syncs to atomic time — done! BEAST MODE (Premium Sync): Need faster sync? Watch a short rewarded video to activate Beast Mode — our enhanced signal algorithm for quicker, more reliable synchronization. Unlimited use, no subscriptions. SMART REMINDERS: Set local notifications to remind you to sync your watch daily, weekly, bi-weekly, monthly or custom. Never lose atomic precision again. OFFLINE & ACCURATE: • All signals generated locally — no internet required for sync • Optional NTP time source sync for maximum accuracy when online • Last known time cached for offline use USER-FRIENDLY DESIGN: • Dark/Light theme (auto-switch) • Universal positioning guide with animated signal waves • Simple 4-step flow, no brand selection needed • 16 languages supported PRIVACY FIRST: • No location access required • No personal data collected • No account registration needed COMPATIBLE WITH: Casio G-Shock, Pro Trek, Edifice • Citizen Eco-Drive • Lacrosse Technology • Junghans Mega • Braun watches • And any watch supporting WWVB/DCF77/JJY/MSF/BPC signals. TIPS FOR SUCCESS: • Use maximum phone volume during sync • Keep phone and watch still, 2-10 cm apart • Avoid metal surfaces and electronic interference DISCLAIMER: Atomic Sync is a third-party tool and is not affiliated with, endorsed by, or connected to Casio, Citizen, or any watch manufacturer. Time signal emulation is for personal use only. Success depends on watch model, environment, and device hardware.

Screenshots

Atomic Clock PRO4 screens
Atomic Sync3 screens

Verdict

The call

The clearest difference is in-app purchases: Atomic Sync at none against Atomic Clock PRO's 2. Atomic Sync also leads on update cadence (fortnightly vs every 3 months). On price, ads, 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. Atomic Clock PRO sells 2 in-app purchases, starting at $1.99 per month. Atomic Sync asks for nothing beyond the download.

UpkeepUpdate frequency

Atomic Clock PRO ships an update every 3 months, Atomic Sync fortnightly. The most recent releases landed on September 26, 2026 and September 19, 2026 respectively.

Scorecard2 real differences · 8 level
Atomic Clock PRO versus Atomic Sync: the parameters behind the verdict, then further details
ParameterAtomic Clock PROAtomic Sync
PriceFreeFree
Rating4.7 (10K ratings) — better—
Positive reviews72.7% of reviews—
Number of ratings10K — better—
Update frequencyEvery 3 monthsFortnightly — better
AdsYesYes
In-app purchasesYesNo — better
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.615.0 — better
Further details — not scored
Size6 MB27 MB
Age rating4+4+
DeveloperBrachmann Online Marketing GmbH & Co. KGSerhii Sereda

Bugs and requests

Atomic Clock PRO

Reported bugs

3 issues
  • Second hand occasionally runs in reverse
  • Digital clock display cuts off on some devices
  • Inconsistent behavior when switching between clock types

Requested features

3 requests
  • Customizable clock face options
  • Ability to set widget on home screen
  • Sync with system clock to automatically update time

Atomic Sync

Not enough reviews yet to summarise bugs or requests.

In-app purchases

2 purchases

Atomic Clock PRO

Subscriptions1
  • Premium$1.991 Month
One-time1
  • Remove Ads$5.99
None

Atomic Sync

No in-app purchases

Questions

Is Atomic Clock PRO free?
Atomic Clock PRO is free to download, with in-app purchases available.
Is Atomic Sync free?
Atomic Sync is free to download, with no in-app purchases.
Do Atomic Clock PRO or Atomic Sync have ads?
Both Atomic Clock PRO and Atomic Sync show ads.
Which is updated more often, Atomic Clock PRO or Atomic Sync?
Atomic Clock PRO ships an update every 3 months, and Atomic Sync fortnightly. Most recently, Atomic Clock PRO was updated on September 26, 2026 and Atomic Sync on September 19, 2026.

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