# Atom Calculator vs Overlap

The clearest difference is price: Overlap at Free against Atom Calculator's $2.99. Overlap also leads on update cadence (every 3 months vs every 35 months). Atom Calculator's advantage is iOS requirement (12.0 vs 15.0). On ads, in-app purchases and device support there is nothing between them.

Overlap is free to download; Atom Calculator costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Atom Calculator ships an update every 35 months, Overlap every 3 months. The most recent releases landed on October 26, 2026 and October 27, 2026 respectively.

## The numbers

| Metric | Atom Calculator | Overlap |
| --- | --- | --- |
| Price | $2.99 | **Free** |
| Rating | — | **[4.8 (876 ratings)](https://appshunter.io/ios/app/overlap-world-clock/id1516950324/reviews)** |
| Number of ratings | — | **876** |
| Positive reviews | — | 67.3% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 35 months | **Every 3 months** |
| Monetization | — | Free |
| Size | 13 MB | 71 MB |
| Requires iOS | **12.0** | 15.0 |
| Devices | iPhone, iPad, iPod | **iPhone, iPad, iPod, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [Gorasiya Vishal Nanjibhai](https://appshunter.io/developer/1287086933) | [Bonobo](https://appshunter.io/developer/666155611) |

## What reviewers say

### Atom Calculator

[App page](https://appshunter.io/ios/app/atom-calculator/id1457529377)

**Features:** macOS Compatibility

**In-app purchases:** none


### Overlap

[App page](https://appshunter.io/ios/app/overlap-world-clock/id1516950324)

Easily find optimal meeting times across different time zones with a visual graph. Set custom availability for each location and sync with your calendar to avoid scheduling conflicts. Share convenient times directly from the app.

**Highlights:** Visual Overlap Graph for meeting times, Customizable availability hours per time zone, Calendar event integration, Multiple time zone display, Time zone renaming, Lock Screen Standby Mode widget

**Features:** Vision Pro support

**In-app purchases:** none

**What reviewers like**

- 💡 Elegant and intuitive interface
- 🚀 Helpful for coordinating meetings across time zones
- 👍 Useful for tracking time differences globally
- 👍 Simple and easy to use
- 👍 Beautiful and sleek design

**What reviewers complain about**

- 🐛 Widget not working
- 🐛 Timezone data not always accurate
- 🐛 Duplicate timezone entries
- 🐛 App crashes and freezes
- 🔋 High CPU usage on Mac

**Reported bugs**

- Timezone data not updating correctly
- Inability to delete unwanted timezones
- Inconsistent behavior across platforms
- Typing issues on Mac version

**Requested features**

- Add option to reorder timezones
- Implement 24-hour clock display
- Allow customization of colors and backgrounds
- Integrate with calendar for scheduling
- Add weather information for each timezone


## Frequently asked questions

### Is Atom Calculator free?

Atom Calculator costs $2.99, with no in-app purchases.

### Is Overlap free?

Overlap is free to download, with no in-app purchases.

### Do Atom Calculator or Overlap have ads?

Neither Atom Calculator nor Overlap shows ads.

### Which is updated more often, Atom Calculator or Overlap?

Atom Calculator ships an update every 35 months, and Overlap every 3 months. Most recently, Atom Calculator was updated on October 26, 2026 and Overlap on October 27, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*