# CenTelum vs OSpectrometer

The clearest difference is in-app purchases: CenTelum at none against OSpectrometer's 2. CenTelum also leads on update cadence (every 4 days vs every 2 weeks). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. OSpectrometer sells 2 in-app purchases, starting at $2.99 per month. CenTelum asks for nothing beyond the download.

CenTelum ships an update every 4 days, OSpectrometer every 2 weeks. The most recent releases landed on October 30, 2026 and October 15, 2026 respectively.

## The numbers

| Metric | CenTelum | OSpectrometer |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[2.0 (4 ratings)](https://appshunter.io/ios/app/ospectrometer/id6446124449/reviews)** |
| Number of ratings | — | **4** |
| Positive reviews | — | 0.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 4 days** | Every 2 weeks |
| Monetization | — | Free with in-app purchases |
| Size | 4 MB | 71 MB |
| Requires iOS | **14.1** | 15.1 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Cenango Financial, LLC](https://appshunter.io/developer/626142722) | [NANO ELECTRONICS RESEARCH MUHENDISLIK ARASTIRMA GELISTIRME LIMITED SIRKETI](https://appshunter.io/developer/1674573382) |

## What reviewers say

### CenTelum

[App page](https://appshunter.io/ios/app/centelum/id6446116286)

**Features:** macOS Compatibility

**In-app purchases:** none


### OSpectrometer

[App page](https://appshunter.io/ios/app/ospectrometer/id6446124449)

This app uses your device's camera and screen to perform basic optical spectroscopy. Analyze the visible light spectrum of objects, map light wavelengths to RGB values, and save or share your findings. It functions offline without external hardware.

**Highlights:** Visible light spectrum analysis, RGB color value mapping, Wavelength selection and scanning, Front camera reflection sensing, Save and share results, Offline functionality

**Features:** Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| month | $2.99 | per month |
| year | $9.99 | per year |


## Frequently asked questions

### Is CenTelum free?

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

### Is OSpectrometer free?

OSpectrometer is free to download, with in-app purchases available.

### Do CenTelum or OSpectrometer have ads?

Neither CenTelum nor OSpectrometer shows ads.

### Which is updated more often, CenTelum or OSpectrometer?

CenTelum ships an update every 4 days, and OSpectrometer every 2 weeks. Most recently, CenTelum was updated on October 30, 2026 and OSpectrometer on October 15, 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.*