Comparison

Atomic Exact Time vs Simple Clock JP

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

Head to head
About

Atomic Exact Time

Synchronize your device's clock with network time sources, view its offset, and use a corrected display. Features include countdown timers, team targets, and world clocks. Optional Pro plans offer advanced features and ad removal.

Highlights
  • Network time synchronization
  • Offset and uncertainty measurement
  • Corrected clock display
  • Countdown timers
  • Team countdown sharing
  • World clocks
  • Home-screen widget
Features
Read full description

See your device clock in context with Atomic Exact Time. Compare it with network time sources, view the measured offset and estimated uncertainty, and use a corrected clock display. Start with the free clock and synchronization tools. The free version includes ads. Optional Pro plans remove ads and unlock precision targets, team countdowns, detailed accuracy reports, Theme Studio, timecode and export tools. Prepare a start: choose an exact time or a duration, check calibration and notification permissions, and test the sound before starting. Save, edit, duplicate and reorder your frequent targets. Share a team target through a link or QR code. Each participant uses their own device calibration. Participant attendance and location are not tracked. Use world clocks, Studio Mode, accessibility preferences and a home-screen widget that shows the latest calibration. Choose from 15 interface languages. Timing accuracy depends on network conditions, device behavior and measurement quality. Uncertainty is an estimate, not a guarantee. Keep the app open for the best countdown timing. Background notification delivery depends on the operating system. Available Pro plans and localized prices are supplied by your store. Monthly and yearly subscriptions renew automatically until canceled in store account settings. A lifetime purchase is a single payment when offered. Restore Purchases is available. No app account is required. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

Simple Clock JP

Features
Read full description

Simple Clock JP shows the current time in large, bold digits, easy to read at a glance from across the room or the stage. Just open the app and the clock is there. No setup, no complicated controls. Features - Large, easy-to-read time display - Shows hours, minutes, and seconds - Date and day of the week - Simple black background - The screen stays on while the clock is shown - On iPad, resize the window freely and place it next to your sheet music or set list app - Picture in Picture: float a compact clock over any other app - No ads, no account, no setup Use it as a desk clock, at work, at events, or on stage whenever you want to see the time in big numbers. A simple clock made for one thing: showing the time, big.

Screenshots

Atomic Exact Time4 screens
Simple Clock JP1 screens

Verdict

The call

The clearest difference is in-app purchases: Simple Clock JP at none against Atomic Exact Time's 3. Simple Clock JP also leads on ads (none vs shown). Atomic Exact Time's advantage is device support (4 vs 2). On price, update cadence 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 Exact Time sells 3 in-app purchases, starting at $2.99 per month. Simple Clock JP asks for nothing beyond the download.

UpkeepUpdate frequency

Atomic Exact Time ships an update every 5 weeks, Simple Clock JP every 4 weeks. The most recent releases landed on November 6, 2026 and October 31, 2026 respectively.

Scorecard3 real differences · 6 level
Atomic Exact Time versus Simple Clock JP: the parameters behind the verdict, then further details
ParameterAtomic Exact TimeSimple Clock JP
PriceFreeFree
Rating4.0 (1 ratings) — better—
Number of ratings1 — better—
Update frequencyEvery 5 weeksEvery 4 weeks — better
AdsYesNo — better
In-app purchasesYesNo — better
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, Mac, Apple TV — betteriPhone, iPad
Requires iOS16.4 — better17.0
Further details — not scored
Size56 MB0 MB
Age rating4+4+
DeveloperSUPER KIM KIMYA VE TEKSTIL SANAYI TICARET LIMITED SIRKETIKantaro Kobayashi

In-app purchases

3 purchases

Atomic Exact Time

Subscriptions2
  • Atomic Exact Time Pro7 Days trial$2.991 Month
  • Pro Yearly$19.991 Year
One-time1
  • Atomic Exact Time Pro$2.99
None

Simple Clock JP

No in-app purchases

Questions

Is Atomic Exact Time free?
Atomic Exact Time is free to download, with in-app purchases available.
Is Simple Clock JP free?
Simple Clock JP is free to download, with no in-app purchases.
Do Atomic Exact Time or Simple Clock JP have ads?
Atomic Exact Time shows ads; Simple Clock JP does not.
Which is updated more often, Atomic Exact Time or Simple Clock JP?
Atomic Exact Time ships an update every 5 weeks, and Simple Clock JP every 4 weeks. Most recently, Atomic Exact Time was updated on November 6, 2026 and Simple Clock JP on October 31, 2026.

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