# Set Theory Clock (BerlinClock) vs eTCH Sync Time

The clearest difference is update cadence: eTCH Sync Time at monthly against Set Theory Clock (BerlinClock)'s every 129 months. eTCH Sync Time also leads on device support (3 vs 1) and iOS requirement (9.3 vs 17.6). On price, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Set Theory Clock (BerlinClock) ships an update every 129 months, eTCH Sync Time monthly. Both last shipped on September 9, 2026.

## The numbers

| Metric | Set Theory Clock (BerlinClock) | eTCH Sync Time |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.0 (2 ratings)](https://appshunter.io/ios/app/set-theory-clock-berlinclock/id972665637/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 129 months | **Monthly** |
| Monetization | Free | — |
| Size | 2 MB | 1 MB |
| Requires iOS | 17.6 | **9.3** |
| Devices | iPhone | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Stefan Neumann](https://appshunter.io/developer/972665636) | [GCtronic Sagl](https://appshunter.io/developer/619822096) |

## What reviewers say

### Set Theory Clock (BerlinClock)

[App page](https://appshunter.io/ios/app/set-theory-clock-berlinclock/id972665637)

This app displays time using the unique Berlin Clock system, featuring 24 lamps arranged in four rows to represent hours and minutes. It offers a visually distinct way to tell time, with lamps lighting up sequentially to indicate the passing of time.

**Highlights:** 24-lamp display, Hour representation (5-hour and 1-hour lamps), Minute representation (5-minute and 1-minute lamps), Sequential lamp lighting, Unique time visualization

**Features:** macOS Compatibility

**In-app purchases:** none


### eTCH Sync Time

[App page](https://appshunter.io/ios/app/etch-sync-time/id1125886335)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Set Theory Clock (BerlinClock) free?

Set Theory Clock (BerlinClock) is free to download, with no in-app purchases.

### Is eTCH Sync Time free?

eTCH Sync Time is free to download, with no in-app purchases.

### Do Set Theory Clock (BerlinClock) or eTCH Sync Time have ads?

Neither Set Theory Clock (BerlinClock) nor eTCH Sync Time shows ads.

### Which is updated more often, Set Theory Clock (BerlinClock) or eTCH Sync Time?

Set Theory Clock (BerlinClock) ships an update every 129 months, and eTCH Sync Time monthly. Most recently, Set Theory Clock (BerlinClock) was updated on September 9, 2026 and eTCH Sync Time on September 9, 2026.

---

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