Comparison

Mars 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

Mars

Features
Read full description

Humanity’s fascination with the Red Planet has never been stronger. With the completely reimagined "Mars: Curiosity" app, we bring the frontiers of space exploration directly to your fingertips through a premium, state-of-the-art experience. Witness Mars as if you were standing on its dusty plains. Our latest update introduces a stunning modern interface featuring glassmorphism elements, dynamic background animations, and an overall design language inspired by the future of space travel. WHAT’S NEW & REIMAGINED: SMART SEARCH & DISCOVERY: Quickly find exactly what you’re looking for with our new global search feature in both the Browse and Video sections. IMMERSIVE VIDEO EXPERIENCE: Watch Curiosity’s journey in high-definition with our all-new video player. Now supporting landscape mode for a true cinema feel, smart autoplay with preview protection, and an elegant Apple TV-inspired layout. MODERN DESIGN SYSTEM: Experience a "alive" interface with subtle stars animations, glass-like cards, and haptic feedback that makes exploring feel tactile and premium. KEY FEATURES: EXPLORE (BROWSE): Navigate through hundreds of official NASA photos with ease. Toggle between grid and list views, shuffle your findings, and search specifically for the missions that interest you most. CINEMATIC SLIDESHOW: Lose yourself in the Martian landscape. Browse full-screen, high-resolution imagery that makes you feel truly present on the planet. HD VIDEO ARCHIVE: Dive deep into Gale Crater, learn about Curiosity’s historic achievements, and explore over 50 years of Martian research through curated video content. INTERACTIVE GALLERY: Examine every detail with intuitive pinch-to-zoom gestures and high-contrast viewing modes. 3D MODELS: Step into the third dimension with interactive models that bring Martian topography and hardware to life. Whether you are a casual observer or a dedicated space enthusiast, Mars: Curiosity provides a compact, powerful, and visually stunning window into the future of our species on another world.

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

Mars4 screens
Stars Units Sizes Objects4 screens

Verdict

The call

The clearest difference is update cadence: Stars Units Sizes Objects at every 4 months against Mars's every 32 months. Stars Units Sizes Objects also leads on iOS requirement (11.0 vs 17.0). On price, ads, 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

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Mars ships an update every 32 months, Stars Units Sizes Objects every 4 months. The most recent releases landed on October 16, 2026 and September 22, 2026 respectively.

Scorecard2 real differences · 8 level
Mars versus Stars Units Sizes Objects: the parameters behind the verdict, then further details
ParameterMarsStars Units Sizes Objects
PriceFreeFree
Rating—4.2 (5 ratings) — better
Positive reviews—80.0% of reviews
Number of ratings—5 — better
Update frequencyEvery 32 monthsEvery 4 months — better
AdsYesYes
In-app purchasesNoNo
Monetization—Ad-supported
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS17.011.0 — better
Further details — not scored
Size108 MB124 MB
Age rating9+4+
DeveloperAlparslan TopbasMudarmeen Munlin

In-app purchases

None

Mars

No in-app purchases

None

Stars Units Sizes Objects

No in-app purchases

Questions

Is Mars free?
Mars is free to download, 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 Mars or Stars Units Sizes Objects have ads?
Both Mars and Stars Units Sizes Objects show ads.
Which is updated more often, Mars or Stars Units Sizes Objects?
Mars ships an update every 32 months, and Stars Units Sizes Objects every 4 months. Most recently, Mars was updated on October 16, 2026 and Stars Units Sizes Objects on September 22, 2026.

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