Comparison

Big Time Clock vs Atomic Exact Time

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

Head to head
About

Big Time Clock

Transform your device into a large, easy-to-read full-screen clock for any room. Enjoy a clear display with customizable typography and orientation, perfect for a nightstand or desk. This app offers a one-time purchase with all features unlocked, no ads or subscriptions.

Highlights
  • Full-screen digital clock
  • Elegant analog face
  • Always-on display
  • Portrait and landscape modes
  • Customizable typography
  • Day and date display
Features
Read full description

Big Time Clock turns your iPhone or iPad into a full-screen clock you can read from right across the room — on a nightstand, a desk, or a kitchen counter. Pay once and it's yours forever. No subscriptions, no in-app purchases, no ads — every feature included. Set it up once and the app remembers: your clock face, your time format, your theme. Open it and the clock has the screen to itself — settings live on their own page, a tap away. THE CLOCK • Full-screen digital clock with massive, easy-to-read numerals • Elegant analog face with a smoothly sweeping red second hand • 12-hour or 24-hour time • Seconds sized to read at a glance — tint them, or hide them completely • Day and date, on or off • Light or bold typography • Dark or light theme — deep black for the bedroom, soft paper-white for daylight ALWAYS ON, ALWAYS YOURS • The screen stays awake — it never locks while the clock is up • Every setting is remembered, so it opens exactly how you left it • Tap the clock, then the gear, to change anything — then it's just the time again • Reset to the default view whenever you want a clean slate • Portrait or landscape — just rotate your device • At home on a bedside table, a desk, a kitchen counter, in a gym or a studio — or on an old iPhone or iPad reborn as a dedicated clock BUILT RIGHT • Pay once, own it for life — the price you see is everything • No subscriptions, no in-app purchases, no upsells • No ads, ever • Megabytes, not gigabytes — no ad libraries, no analytics SDKs, nothing that isn't the app itself • No tracking, no accounts, no data collection — nothing about you ever leaves your device • Designed for iPhone and iPad Download Big Time Clock and always know the time at a glance.

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/

Screenshots

Big Time Clock4 screens
Atomic Exact Time4 screens

Verdict

The call

The clearest difference is price: Atomic Exact Time at Free against Big Time Clock's $2.00. Atomic Exact Time also leads on device support (4 vs 2) and iOS requirement (16.4 vs 18.6). Big Time Clock's advantage is rating (5.0 vs 4.0) and in-app purchases (none vs 3). On update cadence 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

Atomic Exact Time is free to download; Big Time Clock costs $2.00 up front. Atomic Exact Time sells 3 in-app purchases, starting at $2.99 per month. Big Time Clock asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Big Time Clock holds the better App Store score, 5.0 against 4.0. Both are backed by a comparable volume of ratings — 3 and 1 respectively.

UpkeepUpdate frequency

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

Scorecard8 real differences · 2 level
Big Time Clock versus Atomic Exact Time: the parameters behind the verdict, then further details
ParameterBig Time ClockAtomic Exact Time
Price$2.00Free — better
Rating5.0 (3 ratings) — better4.0 (1 ratings)
Positive reviews100.0% of reviews—
Number of ratings3 — better1
Update frequencyEvery 4 weeks — betterEvery 5 weeks
AdsNo — betterYes
In-app purchasesNo — betterYes
MonetizationPaidFree with in-app purchases — better
DevicesiPhone, iPadiPhone, iPad, Mac, Apple TV — better
Requires iOS18.616.4 — better
Further details — not scored
Size1 MB56 MB
Age rating4+4+
DeveloperMatthew AverySUPER KIM KIMYA VE TEKSTIL SANAYI TICARET LIMITED SIRKETI

Customer experience

Big Time Clock

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Atomic Exact Time

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

Big Time Clock

No 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

Questions

Is Big Time Clock free?
Big Time Clock costs $2.00, with no in-app purchases.
Is Atomic Exact Time free?
Atomic Exact Time is free to download, with in-app purchases available.
Which has better reviews, Big Time Clock or Atomic Exact Time?
Big Time Clock is rated higher. Big Time Clock averages 5.0 out of 5 from 3 ratings, while Atomic Exact Time averages 4.0 from 1 ratings.
Do Big Time Clock or Atomic Exact Time have ads?
Atomic Exact Time shows ads; Big Time Clock does not.
Which is updated more often, Big Time Clock or Atomic Exact Time?
Big Time Clock ships an update every 4 weeks, and Atomic Exact Time every 5 weeks. Most recently, Big Time Clock was updated on November 5, 2026 and Atomic Exact Time on November 6, 2026.

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