# iCSC vs Light Pollution Map

The clearest difference is review sentiment: iCSC at 84% against Light Pollution Map's 14%. iCSC also leads on in-app purchases (none vs 6) and rating (4.8 vs 4.5). Light Pollution Map's advantage is update cadence (every 3 weeks vs every 2 months) and chart position (#165 vs unranked). On price, ads and device support there is nothing between them.

Both are free to download. Light Pollution Map sells 6 in-app purchases, starting at $9.99 per year. iCSC asks for nothing beyond the download.

iCSC holds the better App Store score, 4.8 against 4.5. That said, the two scores are not equally well evidenced: iCSC has 1.6K ratings behind it against 251, so its average is the more settled of the two. Written reviews point the same way: 84% of iCSC's written reviews are positive against 14% of Light Pollution Map's.

iCSC ships an update every 2 months, Light Pollution Map every 3 weeks. The most recent releases landed on October 29, 2026 and October 26, 2026 respectively.

## The numbers

| Metric | iCSC | Light Pollution Map |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (1.6K ratings)](https://appshunter.io/ios/app/icsc-clear-sky-chart-viewer/id877416121/reviews)** | [4.5 (251 ratings)](https://appshunter.io/ios/app/light-pollution-map-dark-sky/id1200379779/reviews) |
| Number of ratings | **1.6K** | 251 |
| Positive reviews | **84.2% of reviews** | 14.1% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 3 weeks** |
| Monetization | **Free** | Free with in-app purchases |
| Best chart rank | — | **#165** |
| Size | 19 MB | 93 MB |
| Requires iOS | **11.0** | 17.0 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | +4 | 4+ |
| Developer | [Random Widgets LLC](https://appshunter.io/developer/1689907576) | [Dunbar Technology, LLC](https://appshunter.io/developer/1200379778) |

## 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


### Light Pollution Map

[App page](https://appshunter.io/ios/app/light-pollution-map-dark-sky/id1200379779)

**Currently charting:** #165 Top Grossing · Weather, #180 Top Free · Weather (US App Store)

Discover optimal locations for stargazing and astrophotography with a detailed light pollution map. Get real-time alerts for celestial events like meteor showers and auroras, track the ISS, and access daily astronomy photos. Enhance your night sky observations with comprehensive tools and information.

**Highlights:** Interactive light pollution map, Aurora borealis live map and alerts, Meteor shower and super moon alerts, ISS tracker with live updates, Moon phases and information, Astronomy photo of the day

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

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Version | $9.99 | per year |
| Pro Version | $14.99 | per year |
| Pro Version | $19.99 | per year |
| Pro Version | $29.99 | per year |
| Pro Version Upgrade Discounted | $8.99 | one-time |
| Pro Version Upgrade | $9.99 | one-time |

**What reviewers like**

- 👍 Clear detailed satellite views
- 🚀 Works with barely any signal
- 📊 Useful map with latest data
- 🌌 Helps with astrophotography

**What reviewers complain about**

- 🐛 Crashes on opening the map
- 🐛 Crashes after locating user's position
- 🔍 No legend for map colors
- 💰 Tries to get users to upgrade to premium

**Reported bugs**

- App crashes when opening light pollution map
- App crashes after locating user's position
- Cloud coverage feature not working as expected

**Requested features**

- Add Bortle rating information
- Improve cloud coverage feature
- Fix crashing issues


## Frequently asked questions

### Is iCSC free?

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

### Is Light Pollution Map free?

Light Pollution Map is free to download, with in-app purchases available.

### Which has better reviews, iCSC or Light Pollution Map?

iCSC is rated higher. iCSC averages 4.8 out of 5 from 1.6K ratings, while Light Pollution Map averages 4.5 from 251 ratings.

### Do iCSC or Light Pollution Map have ads?

Neither iCSC nor Light Pollution Map shows ads.

### Which is updated more often, iCSC or Light Pollution Map?

iCSC ships an update every 2 months, and Light Pollution Map every 3 weeks. Most recently, iCSC was updated on October 29, 2026 and Light Pollution Map on October 26, 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.*