# SDO Viewer vs CassiniMIMI

The clearest difference is rating: CassiniMIMI at 5.0 against SDO Viewer's 3.0. CassiniMIMI also leads on review sentiment (100% vs 60%) and update cadence (weekly vs every 2 months). On price, ratings volume, 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.

CassiniMIMI holds the better App Store score, 5.0 against 3.0. Both are backed by a comparable volume of ratings — 5 and 2 respectively. Written reviews point the same way: 60% of SDO Viewer's written reviews are positive against 100% of CassiniMIMI's.

SDO Viewer ships an update every 2 months, CassiniMIMI weekly. The most recent releases landed on October 7, 2026 and October 8, 2026 respectively.

## The numbers

| Metric | SDO Viewer | CassiniMIMI |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.0 (5 ratings)](https://appshunter.io/ios/app/sdo-viewer/id913723111/reviews) | **[5.0 (2 ratings)](https://appshunter.io/ios/app/cassinimimi/id1153077273/reviews)** |
| Number of ratings | **5** | 2 |
| Positive reviews | 60.0% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | **Weekly** |
| Monetization | Free | Free |
| Size | 6 MB | 19 MB |
| Requires iOS | 13.0 | **8.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Jérôme Diaz](https://appshunter.io/developer/334987620) | [Johns Hopkins University Applied Physics Laboratory](https://appshunter.io/developer/473217885) |

## 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


### CassiniMIMI

[App page](https://appshunter.io/ios/app/cassinimimi/id1153077273)

Explore stunning images and data from NASA's Cassini mission to Saturn. This app provides access to energetic particle data, ENA images, and spectrograms from Saturn's magnetosphere. Discover new scientific releases and browse daily updated plots and movies.

**Highlights:** Energetic charged particle environment study, Energetic Neutral Atom (ENA) imaging of Saturn, Spectrograms and plots from particle detectors, Access to NASA's Planetary Data System (PDS), Daily updated plots and movies, Selectable data by source, type, date, and style

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is SDO Viewer free?

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

### Is CassiniMIMI free?

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

### Which has better reviews, SDO Viewer or CassiniMIMI?

CassiniMIMI is rated higher. SDO Viewer averages 3.0 out of 5 from 5 ratings, while CassiniMIMI averages 5.0 from 2 ratings.

### Do SDO Viewer or CassiniMIMI have ads?

Neither SDO Viewer nor CassiniMIMI shows ads.

### Which is updated more often, SDO Viewer or CassiniMIMI?

SDO Viewer ships an update every 2 months, and CassiniMIMI weekly. Most recently, SDO Viewer was updated on October 7, 2026 and CassiniMIMI on October 8, 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.*