Comparison

Interactive Solar System 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

Interactive Solar System

Features
Read full description

Take a thrilling tour of the Solar System with the Interactive Solar System Explorer. Select the planet that you wish to explore and then hit the power button to zoom off to your destination. When you arrive a myriad of interesting facts await you. Tap a button access interesting data about each of the planets, the asteroids and the Earth's moon. Facts include distance from the sun, diameter, mass, and orbital and rotational periods -- all presented in an interactive format. Tap the info button to read interesting facts about each important object in the solar system. Teachers will really like this app. After students have read about the planets, they can tap the quiz button to measure their reading comprehension. In addition to the quiz there is also a word game that helps students review the information presented. Charts and graphs are used to present comparison information about the planets. Interactive Solar System Explorer is available for iOS and tvOS devices. It is just beautiful on a big screen TV and would be a wonderfully exciting tool in any science classroom.

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

Stars Units Sizes Objects4 screens

Verdict

The call

The clearest difference is price: Stars Units Sizes Objects at Free against Interactive Solar System's $1.99. Interactive Solar System's advantage is ads (none vs shown) and update cadence (fortnightly vs every 4 months). On in-app purchases, device support and iOS requirement 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; Interactive Solar System costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Interactive Solar System ships an update fortnightly, Stars Units Sizes Objects every 4 months. The most recent releases landed on September 18, 2026 and September 7, 2026 respectively.

Scorecard3 real differences · 7 level
Interactive Solar System versus Stars Units Sizes Objects: the parameters behind the verdict, then further details
ParameterInteractive Solar SystemStars Units Sizes Objects
Price$1.99Free — better
Rating4.2 (5 ratings) — better
Positive reviews80.0% of reviews
Number of ratings5 — better
Update frequencyFortnightly — betterEvery 4 months
AdsNo — betterYes
In-app purchasesNoNo
MonetizationAd-supported
DevicesiPad, Apple TViPhone, iPad, iPod — better
Requires iOS12.011.0 — better
Further details — not scored
Size52 MB124 MB
Age rating4+4+
DeveloperVentura Educational SystemsMudarmeen Munlin

In-app purchases

None

Interactive Solar System

No in-app purchases

None

Stars Units Sizes Objects

No in-app purchases

Questions

Is Interactive Solar System free?
Interactive Solar System costs $1.99, with no in-app purchases.
Is Stars Units Sizes Objects free?
Stars Units Sizes Objects is free to download, with no in-app purchases.
Do Interactive Solar System or Stars Units Sizes Objects have ads?
Stars Units Sizes Objects shows ads; Interactive Solar System does not.
Which is updated more often, Interactive Solar System or Stars Units Sizes Objects?
Interactive Solar System ships an update fortnightly, and Stars Units Sizes Objects every 4 months. Most recently, Interactive Solar System was updated on September 18, 2026 and Stars Units Sizes Objects on September 7, 2026.

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