Stars Units Sizes Objects vs First Light
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Stars Units Sizes Objects
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.
- 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
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Size of the smallest to largest objects and stars. Compare the size of objects in the universe. Object images. Pinch/Zoom image. Pan/Move image. Rotate image. Double tap to reset an image. From the smallest to the largest one. From planck length to observable universe. From Yoctometre, Zeptometre, Attometre, Femtometre, Picometre, Nanometre, Micro, Millimetre, Centimetre, Metre, KiloMetre, Lightyear, Parsecs, Billion Lightyears to 93 Billion Lightyears. Size of objects, particles, atoms, cells, stars and galaxies. Get to know the stars. Get to know the spaces. get to know the universe. How small is this world. How big is the universe. And How great is the creator. How far is the star distance from earth. Two way 18 distance unit conversion. planck length, yoctometer, zeptometer, attometer, femtometer, picometre, nanometre, micrometre, Millimeter, Centimeter, Meter, Kilometer, Inch, Foot, Mile, Astronomical, Lightyear, Parsecs. Perform auto conversion when picker is changed. Share conversion result. Reset unit convertor.
First Light
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.
- 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
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Look up. What you're seeing isn't the night sky. It's the afterglow of the Big Bang, captured by three of the most important space missions ever launched. First Light turns real cosmic microwave background data from COBE, WMAP, and Planck into an immersive sky you can explore by simply moving your phone. Pan across the oldest light in the universe. Switch between satellites. Dial through frequency bands and watch the universe shift. This is real data. Real science. And it fits in your pocket.
Screenshots
Verdict
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.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
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.
| Parameter | Stars Units Sizes Objects | First Light |
|---|---|---|
| Price | Free | Free |
| Rating | 4.2 (5 ratings) | 5.0 (3 ratings) — better |
| Positive reviews | 80.0% of reviews | 100.0% of reviews — better |
| Number of ratings | 5 — better | 3 |
| Update frequency | Every 4 months | Every 3 weeks — better |
| Ads | Yes | No — better |
| In-app purchases | No | No |
| Monetization | Ad-supported | Free — better |
| Devices | iPhone, iPad, iPod — better | iPhone |
| Requires iOS | 11.0 — better | 17.0 |
| Further details — not scored | ||
| Size | 124 MB | 75 MB |
| Age rating | 4+ | 4+ |
| Developer | Mudarmeen Munlin | Thomas Sola |
Customer experience
Stars Units Sizes Objects
First Light
In-app purchases
Stars Units Sizes Objects
No in-app purchases
First Light
No in-app purchases
Questions
Is Stars Units Sizes Objects free?
Is First Light free?
Which has better reviews, Stars Units Sizes Objects or First Light?
Do Stars Units Sizes Objects or First Light have ads?
Which is updated more often, Stars Units Sizes Objects or First Light?
Other comparisons
