# Retül Fit vs CORE Thermal Sensor

The clearest difference is monetization model: CORE Thermal Sensor at free against Retül Fit's free with in-app purchases. CORE Thermal Sensor also leads on review sentiment (19% vs 0%) and ratings volume (35 vs 5). Retül Fit's advantage is update cadence (fortnightly vs every 2 months). On price, rating, 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.

On the App Store both sit at effectively the same score — 2.6 for Retül Fit against 2.5 for CORE Thermal Sensor. That said, the two scores are not equally well evidenced: CORE Thermal Sensor has 35 ratings behind it against 5, so its average is the more settled of the two. Written reviews are what separate them: 0% of Retül Fit's written reviews are positive against 19% of CORE Thermal Sensor's.

Retül Fit ships an update fortnightly, CORE Thermal Sensor every 2 months. The most recent releases landed on October 11, 2026 and October 23, 2026 respectively.

## The numbers

| Metric | Retül Fit | CORE Thermal Sensor |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[2.6 (5 ratings)](https://appshunter.io/ios/app/retul-fit/id1434354462/reviews)** | [2.5 (35 ratings)](https://appshunter.io/ios/app/core-thermal-sensor/id1521866309/reviews) |
| Number of ratings | 5 | **35** |
| Positive reviews | 0.0% of reviews | **18.8% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 2 months |
| Monetization | Free with in-app purchases | **Free** |
| Size | 181 MB | 55 MB |
| Requires iOS | 16.2 | **15.1** |
| Devices | iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Specialized Bicycle Components, Inc.](https://appshunter.io/developer/627538437) | [greenteg AG](https://appshunter.io/developer/1510577388) |

## What reviewers say

### Retül Fit

[App page](https://appshunter.io/ios/app/retul-fit/id1434354462)

This app uses advanced technology to collect and analyze rider data, helping retailers and fitters improve comfort, prevent injuries, and enhance performance. It leverages insights from professional athletes to benefit riders of all levels.

**Highlights:** Rider data collection and analysis, Injury prevention guidance, Performance improvement insights, Product decision support, Professional athlete insights, Modern immersive experience

**Features:** macOS Compatibility

**In-app purchases:** none


### CORE Thermal Sensor

[App page](https://appshunter.io/ios/app/core-thermal-sensor/id1521866309)

This app continuously monitors your core body temperature and thermal strain, providing critical data for heat training and optimal race performance. It helps athletes of all levels improve their training and achieve better results.

**Highlights:** Continuous core body temperature monitoring, Real-time Heat Strain Index, Heat Zones for training and racing, Heat Training Load and Adaptation Score, Passive heat training tracking, Data trends and historical analysis, Connectivity with sports devices

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Retül Fit free?

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

### Is CORE Thermal Sensor free?

CORE Thermal Sensor is free to download, with no in-app purchases.

### Which has better reviews, Retül Fit or CORE Thermal Sensor?

Retül Fit is rated higher. Retül Fit averages 2.6 out of 5 from 5 ratings, while CORE Thermal Sensor averages 2.5 from 35 ratings.

### Do Retül Fit or CORE Thermal Sensor have ads?

Neither Retül Fit nor CORE Thermal Sensor shows ads.

### Which is updated more often, Retül Fit or CORE Thermal Sensor?

Retül Fit ships an update fortnightly, and CORE Thermal Sensor every 2 months. Most recently, Retül Fit was updated on October 11, 2026 and CORE Thermal Sensor on October 23, 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.*