# iCSC vs Astrospheric

The clearest difference is in-app purchases: iCSC at none against Astrospheric's 2. iCSC also leads on ratings volume (1.6K vs 481) and iOS requirement (11.0 vs 15.1). Astrospheric's advantage is update cadence (every 2 weeks vs every 2 months) and chart position (#74 vs unranked). On price, rating, review sentiment and ads there is nothing between them.

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

On the App Store both sit at effectively the same score — 4.8 for iCSC against 4.8 for Astrospheric. Both are backed by a comparable volume of ratings — 1.6K and 481 respectively. Written reviews are what separate them: 84% of iCSC's written reviews are positive against 87% of Astrospheric's.

iCSC ships an update every 2 months, Astrospheric every 2 weeks. Both last shipped on October 24, 2026.

## The numbers

| Metric | iCSC | Astrospheric |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (1.6K ratings)](https://appshunter.io/ios/app/icsc-clear-sky-chart-viewer/id877416121/reviews)** | [4.8 (481 ratings)](https://appshunter.io/ios/app/astrospheric/id1166046863/reviews) |
| Number of ratings | **1.6K** | 481 |
| Positive reviews | 84.2% of reviews | **86.8% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 2 weeks** |
| Monetization | **Free** | Freemium |
| Best chart rank | — | **#74** |
| Size | 19 MB | 39 MB |
| Requires iOS | **11.0** | 15.1 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | +4 | 4+ |
| Developer | [Random Widgets LLC](https://appshunter.io/developer/1689907576) | [Daniel Fiordalis](https://appshunter.io/developer/1166046862) |

## What reviewers say

### iCSC

[App page](https://appshunter.io/ios/app/icsc-clear-sky-chart-viewer/id877416121)

This app provides detailed 48-hour sky forecasts for astronomical observation. It helps users find optimal locations and times for clear, dark skies by displaying data on cloud cover, transparency, and more. Save your favorite charts for quick access.

**Highlights:** 48-hour sky forecasts, Cloud cover, transparency, seeing data, Search by location or map, Save favorite charts, Legend for chart interpretation, North American chart coverage

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

**In-app purchases:** none

**What reviewers like**

- 🚀 Awesome
- 🚀 Great
- 🚀 The Best
- 🚀 Great Tool
- 🚀 Works Great !

**What reviewers complain about**

- 🐛 Not supported
- 🐛 Accuracy
- 🐛 no key to charts
- 🐛 NO TOO IMPRESSED
- 🐛 Terrible.

**Reported bugs**

- Crashed on opening a favorite, even after your message says bug is fixed.
- Latest update crashes on Iphone X
- Crashes as soon as I select an observatory/location ever since the update.
- Wish they explained what each category meant in terms of overall ability to see the stars.
- The data isn't bad, but it is all but unusable on my 5th gen iPad Pro 12.9. Tiny text you can't zoom in on.

**Requested features**

- Please add widgets and iPad support
- Can update the forecast more frequent, at least once in the afrernoon
- Search function
- Good app, would love widget


### Astrospheric

[App page](https://appshunter.io/ios/app/astrospheric/id1166046863)

**Currently charting:** #74 Top Grossing · Weather, #170 Top Free · Weather (US App Store)

This app offers advanced weather forecasting and astronomical data for stargazers and astrophotographers. It provides detailed hourly forecasts, cloud and sky transparency reports, and alerts for celestial events. It also includes tools for astronomical societies and offline site setup.

**Highlights:** 84-hour hourly weather forecast, Ensemble cloud forecast, Kp index for Aurora, ISS flyover paths, Integrated smoke forecast, Sky and ground data, Rise and set times, Solar and Lunar eclipse data

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Astrospheric Pro Subscription | $2.99 | per month |
| Astrospheric Pro Subscription | $29.99 | per year |

**What reviewers like**

- 🚀 Precision tool for astrophotography
- 🔍 Detailed weather forecasts
- ⭐ Accurate and reliable
- 💻 Comprehensive data and features
- 📊 Helpful for planning observing sessions

**What reviewers complain about**

- 🐛 Occasional inaccurate forecasts
- 🔍 Missing some weather data (e.g. wind)
- 💰 Subscription required for full functionality
- 🔌 Compatibility issues on some devices

**Reported bugs**

- App crashing or not loading on some devices
- Inconsistent temperature and wind data

**Requested features**

- Notification system for clear skies
- Widgets for quick access to data
- More detailed transparency and seeing data
- Ability to flip east and west in the app


## Frequently asked questions

### Is iCSC free?

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

### Is Astrospheric free?

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

### Which has better reviews, iCSC or Astrospheric?

iCSC is rated higher. iCSC averages 4.8 out of 5 from 1.6K ratings, while Astrospheric averages 4.8 from 481 ratings.

### Do iCSC or Astrospheric have ads?

Neither iCSC nor Astrospheric shows ads.

### Which is updated more often, iCSC or Astrospheric?

iCSC ships an update every 2 months, and Astrospheric every 2 weeks. Most recently, iCSC was updated on October 24, 2026 and Astrospheric on October 24, 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.*