Comparison

Universe in a Nutshell vs Stars Units Sizes Objects

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Universe in a Nutshell

Explore the vastness of the universe, from subatomic particles to distant galaxies, through an interactive, swipe-based journey. Understand true scale by comparing objects and discover fascinating facts about over 250 animated illustrations. Immerse yourself in the cosmos with original music.

Highlights
  • Interactive scale exploration
  • Seamless zooming from 10^-35m to 10^26m
  • Fun facts about objects
  • Explanations for each object
  • Over 250 animated illustrations
  • Original music soundtrack
Features
Currently charting
Read full description

The range of size in the universe, from the tiniest particles to the epic galaxies - we take you on a journey of size that lets you explore it all with a single swipe. How big is a planet, compared to a human? And how small is an atom really? You can’t fully wrap your head around the scope of things by just reading about them – so this app lets you experience them in comparison to get a feeling for their true scale. By simply swiping you can zoom in and out all the way from the world of fundamental particles up to the largest stars at the edge of the observable universe. Seamless zooming between the scales of 10^-35 meters to 10^26 meters (no math required) Amazing fun facts for various scale levels, like the smallest bacterium and the largest black hole Tap any object for an explanation of what it is and how it works Beautifully animated illustration of more than 250 objects Original Kurzgesagt music to complement your experience

About

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.

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
Read full description

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.

Screenshots

Universe in a Nutshell4 screens
Stars Units Sizes Objects4 screens

Verdict

The call

The clearest difference is price: Stars Units Sizes Objects at Free against Universe in a Nutshell's $2.99. Stars Units Sizes Objects also leads on iOS requirement (11.0 vs 13.0). Universe in a Nutshell's advantage is rating (4.9 vs 4.3) and ads (none vs shown). On in-app purchases and device support 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

CostPrice · In-app purchases · Ads · Monetization

Stars Units Sizes Objects is free to download; Universe in a Nutshell costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Universe in a Nutshell holds the better App Store score, 4.9 against 4.3. That said, the two scores are not equally well evidenced: Universe in a Nutshell has 2.5K ratings behind it against 6, so its average is the more settled of the two. Written reviews point the same way: 89% of Universe in a Nutshell's written reviews are positive against 80% of Stars Units Sizes Objects's.

UpkeepUpdate frequency

Universe in a Nutshell ships an update every 4 days, Stars Units Sizes Objects every 4 months. Both last shipped on October 31, 2026.

Scorecard9 real differences · 2 level
Universe in a Nutshell versus Stars Units Sizes Objects: the parameters behind the verdict, then further details
ParameterUniverse in a NutshellStars Units Sizes Objects
Price$2.99Free — better
Rating4.9 (2.5K ratings) — better4.3 (6 ratings)
Positive reviews89.1% of reviews — better80.0% of reviews
Number of ratings2.5K — better6
Update frequencyEvery 4 days — betterEvery 4 months
AdsNo — betterYes
In-app purchasesNoNo
MonetizationFree — betterAd-supported
Best chart rank#51 — better—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS13.011.0 — better
Further details — not scored
Size320 MB124 MB
Age rating4+4+
Developerin a nutshell - kurzgesagt GmbHMudarmeen Munlin

Customer experience

Universe in a Nutshell

All ratings2,508 ratings
Positive97.6%
Neutral0.8%
Negative1.6%
Written reviews449 reviews
Positive89.1%
Neutral3.1%
Negative7.8%

Stars Units Sizes Objects

All ratings6 ratings
Positive83.3%
Neutral0.0%
Negative16.7%
Written reviews5 reviews
Positive80.0%
Neutral0.0%
Negative20.0%

Bugs and requests

Universe in a Nutshell

Reported bugs

2 issues
  • Crashes on launch for some users
  • Overlapping hit boxes make it difficult to select certain objects

Requested features

6 requests
  • Add more objects to explore (e.g. Uranus, Eris, more moons, etc.)
  • Implement a search function to quickly find specific objects
  • Add the ability to compare multiple objects side-by-side
  • Include more in-depth scientific information and facts
  • Provide an option to have the descriptions read aloud
Show 1 more
  • Improve the smoothness of zooming and panning

Stars Units Sizes Objects

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

Universe in a Nutshell

No in-app purchases

None

Stars Units Sizes Objects

No in-app purchases

Questions

Is Universe in a Nutshell free?
Universe in a Nutshell costs $2.99, with no in-app purchases.
Is Stars Units Sizes Objects free?
Stars Units Sizes Objects is free to download, with no in-app purchases.
Which has better reviews, Universe in a Nutshell or Stars Units Sizes Objects?
Universe in a Nutshell is rated higher. Universe in a Nutshell averages 4.9 out of 5 from 2.5K ratings, while Stars Units Sizes Objects averages 4.3 from 6 ratings.
Do Universe in a Nutshell or Stars Units Sizes Objects have ads?
Stars Units Sizes Objects shows ads; Universe in a Nutshell does not.
Which is updated more often, Universe in a Nutshell or Stars Units Sizes Objects?
Universe in a Nutshell ships an update every 4 days, and Stars Units Sizes Objects every 4 months. Most recently, Universe in a Nutshell was updated on October 31, 2026 and Stars Units Sizes Objects on October 31, 2026.

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