# Stars Units Sizes Objects vs First Light

The clearest difference is rating: First Light at 5.0 against Stars Units Sizes Objects's 4.2. First Light also leads on ads (none vs shown) and update cadence (every 3 weeks vs every 4 months). Stars Units Sizes Objects's advantage is device support (3 vs 1) and iOS requirement (11.0 vs 17.0). On price, ratings volume 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.

First Light holds the better App Store score, 5.0 against 4.2. Both are backed by a comparable volume of ratings — 5 and 3 respectively. Written reviews point the same way: 80% of Stars Units Sizes Objects's written reviews are positive against 100% of First Light's.

Stars Units Sizes Objects ships an update every 4 months, First Light every 3 weeks. The most recent releases landed on September 22, 2026 and October 15, 2026 respectively.

## The numbers

| Metric | Stars Units Sizes Objects | First Light |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.2 (5 ratings)](https://appshunter.io/ios/app/stars-units-sizes-objects/id1576148571/reviews) | **[5.0 (3 ratings)](https://appshunter.io/ios/app/first-light-cosmic-viewer/id6780022564/reviews)** |
| Number of ratings | **5** | 3 |
| Positive reviews | 80.0% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | Every 4 months | **Every 3 weeks** |
| Monetization | Ad-supported | **Free** |
| Size | 124 MB | 75 MB |
| Requires iOS | **11.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Mudarmeen Munlin](https://appshunter.io/developer/1348165664) | [Thomas Sola](https://appshunter.io/developer/6780022566) |

## What reviewers say

### Stars Units Sizes Objects

[App page](https://appshunter.io/ios/app/stars-units-sizes-objects/id1576148571)

Explore the vastness of the universe, from the smallest particles to the largest cosmic structures. Compare object sizes, view detailed images, and perform unit conversions across a wide range of astronomical scales. Learn about stars, galaxies, and the incredible distances between them.

**Highlights:** Compare object sizes, View object images, Pinch/Zoom and Pan images, Unit conversion for distances, Explore scales from Planck length to observable universe, Learn about stars and galaxies

**Features:** macOS Compatibility

**In-app purchases:** none


### First Light

[App page](https://appshunter.io/ios/app/first-light-cosmic-viewer/id6780022564)

Explore the universe's earliest light with real cosmic microwave background data. Pan across the oldest light in the universe, switch between satellites, and observe shifts in frequency bands. This educational app brings real science and cosmic history to your mobile device.

**Highlights:** Explore cosmic microwave background data, Immersive sky exploration via phone movement, Switch between COBE, WMAP, and Planck satellites, Adjust frequency bands to see universe shifts, Utilizes real scientific data

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

**In-app purchases:** none


## Frequently asked questions

### Is Stars Units Sizes Objects free?

Stars Units Sizes Objects is free to download, with no in-app purchases.

### Is First Light free?

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

### Which has better reviews, Stars Units Sizes Objects or First Light?

First Light is rated higher. Stars Units Sizes Objects averages 4.2 out of 5 from 5 ratings, while First Light averages 5.0 from 3 ratings.

### Do Stars Units Sizes Objects or First Light have ads?

Stars Units Sizes Objects shows ads; First Light does not.

### Which is updated more often, Stars Units Sizes Objects or First Light?

Stars Units Sizes Objects ships an update every 4 months, and First Light every 3 weeks. Most recently, Stars Units Sizes Objects was updated on September 22, 2026 and First Light 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.*