# SDO Viewer vs CREDO Detector

The clearest difference is review sentiment: SDO Viewer at 60% against CREDO Detector's 0%. SDO Viewer also leads on rating (3.0 vs 1.4). CREDO Detector's advantage is iOS requirement (11.0 vs 13.0). On price, ratings volume, update cadence and ads there is nothing between them.

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

SDO Viewer holds the better App Store score, 3.0 against 1.4. Both are backed by a comparable volume of ratings — 5 and 5 respectively. Written reviews point the same way: 60% of SDO Viewer's written reviews are positive against 0% of CREDO Detector's.

Both ship on a similar rhythm, roughly every 2 months. The most recent releases landed on October 7, 2026 and October 1, 2026 respectively.

## The numbers

| Metric | SDO Viewer | CREDO Detector |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.0 (5 ratings)](https://appshunter.io/ios/app/sdo-viewer/id913723111/reviews)** | [1.4 (5 ratings)](https://appshunter.io/ios/app/credo-detector/id1598629085/reviews) |
| Number of ratings | 5 | 5 |
| Positive reviews | **60.0% of reviews** | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | Every 2 months |
| Monetization | Free | Free |
| Size | 6 MB | 14 MB |
| Requires iOS | 13.0 | **11.0** |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Jérôme Diaz](https://appshunter.io/developer/334987620) | [Michal Frontczak](https://appshunter.io/developer/1598629147) |

## What reviewers say

### SDO Viewer

[App page](https://appshunter.io/ios/app/sdo-viewer/id913723111)

Access and view the latest images from the Solar Dynamics Observatory. Receive push notifications when new images become available, keeping you updated on solar activity.

**Highlights:** Download SDO images, Display latest solar images, Push notifications for new images, Courtesy of NASA/SDO science teams

**Features:** macOS Compatibility

**In-app purchases:** none


### CREDO Detector

[App page](https://appshunter.io/ios/app/credo-detector/id1598629085)

This app enables citizen scientists to contribute to a global cosmic-ray detection network. By using your device's camera, you can help researchers study rare cosmic-ray phenomena, advancing our understanding of cosmology and astrophysics.

**Highlights:** Cosmic-ray particle detection, Global citizen science network, Uses device camera matrix, Publicly available code, Contributes to astrophysics research

**In-app purchases:** none


## Frequently asked questions

### Is SDO Viewer free?

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

### Is CREDO Detector free?

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

### Which has better reviews, SDO Viewer or CREDO Detector?

SDO Viewer is rated higher. SDO Viewer averages 3.0 out of 5 from 5 ratings, while CREDO Detector averages 1.4 from 5 ratings.

### Do SDO Viewer or CREDO Detector have ads?

Neither SDO Viewer nor CREDO Detector shows ads.

### Which is updated more often, SDO Viewer or CREDO Detector?

SDO Viewer ships an update every 2 months, and CREDO Detector every 2 months. Most recently, SDO Viewer was updated on October 7, 2026 and CREDO Detector on October 1, 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.*