# 3demp vs Watch Sensor Logger

The clearest difference is ads: 3demp at none against Watch Sensor Logger's shown. 3demp also leads on update cadence (every 10 months vs every 25 months) and iOS requirement (11.0 vs 17.0). On price, in-app purchases and device support there is nothing between them.

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

3demp ships an update every 10 months, Watch Sensor Logger every 25 months. The most recent releases landed on October 5, 2026 and October 10, 2026 respectively.

## The numbers

| Metric | 3demp | Watch Sensor Logger |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | — | 50.0% of reviews |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | **Every 10 months** | Every 25 months |
| Monetization | — | Free |
| Size | 15 MB | 17 MB |
| Requires iOS | **11.0** | 17.0 |
| Devices | iPhone, iPod | **iPhone, iPad, Apple Watch** |
| Age rating | 4+ | 4+ |
| Developer | [Jang Heesu](https://appshunter.io/developer/469322291) | [yuya kanbetsunawa](https://appshunter.io/developer/1597026161) |

## What reviewers say

### 3demp

[App page](https://appshunter.io/ios/app/3demp/id1036158778)

**In-app purchases:** none


### Watch Sensor Logger

[App page](https://appshunter.io/ios/app/watch-sensor-logger/id1634449655)

Log detailed motion and GPS data from your Apple Watch. Export sensor readings like acceleration, attitude, and location as a CSV file for analysis. This app is exclusively designed for Apple Watch.

**Highlights:** Log sensor data, GPS tracking, Export to CSV, Acceleration logging, Attitude data, Time stamping

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is 3demp free?

3demp is free to download, with no in-app purchases.

### Is Watch Sensor Logger free?

Watch Sensor Logger is free to download, with no in-app purchases.

### Do 3demp or Watch Sensor Logger have ads?

Watch Sensor Logger shows ads; 3demp does not.

### Which is updated more often, 3demp or Watch Sensor Logger?

3demp ships an update every 10 months, and Watch Sensor Logger every 25 months. Most recently, 3demp was updated on October 5, 2026 and Watch Sensor Logger on October 10, 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.*