Comparison

Planet vs COSMOS

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

Head to head
About

Planet

Features
Read full description

Planet turns the solar system into something you can hold, spin, and poke at. Built for curious minds of all ages, it trades walls of text for things you can actually touch: drag through the orbits, tap a world to open it up, and see the real numbers behind it. EXPLORE THE SOLAR SYSTEM Pinch to zoom and drag to pan across the planets in their orbits. Tap any planet — or the Sun — to open its details: diameter, distance from the Sun, day length, and a short description. Then open it as an interactive 3D model you can turn in your hands. BROWSE AND SEARCH Every planet, the Sun, 20 notable moons, and a full overview of the solar system itself — how it formed, what's in it, and where we sit in the Milky Way. Search across all of it: type "Olympus" and you'll land on Mars. MOONS Titan's lakes of liquid methane. Enceladus firing geysers of water into space. Io, the most volcanic world we know. Ganymede, bigger than Mercury. Triton, orbiting backwards because Neptune caught it. COMPARE Put two worlds side by side and watch the scale land. Diameter, distance, day length, year length, gravity, and moons — drawn to their true relative size. Line Earth up against the Sun and see what 109 times wider actually looks like. TEST YOURSELF 135 questions, ten per round, drawn fresh every time. Every answer comes with a one-line explanation of why it's right, so a wrong guess teaches you something. Miss a few and you'll get them back at the end, with the reasons, to review. WEIGH IN, ANYWHERE Enter your weight and see what you'd weigh on every other planet — in kilograms or pounds. Enter your age and find out how many laps of the Sun you'd have made on Mars, or Neptune. SEE THEM IN 3D Load a detailed 3D model of any planet, spin it, and get close. ENGLISH AND PERSIAN Fully translated, including every article and quiz question. Switch language any time in Settings. No accounts. No ads. No data collected. Just the solar system.

About

COSMOS

Explore a real-time 3D model of the solar system, accurately depicting planet positions based on orbital mechanics. Zoom in on celestial bodies, control time to view past or future sky events, and learn details about each planet. This app offers an ad-free, offline experience with a one-time purchase.

Highlights
  • Real-time planet and moon positions
  • Scrub through time for past/future views
  • Photo-realistic textures
  • Adjustable time scale
  • Free exploration with pinch and swipe
  • Detailed information on celestial bodies
Features
Read full description

COSMOS is a solar system you hold in your hand. This is not a decoration. Every planet sits exactly where it is right now, computed from real orbital mechanics. Where is Jupiter tonight? How are Saturn's rings tilted? Open the app — the answer is there. - REAL ORBITS Positions of all 8 planets and the Moon are computed from Keplerian orbital elements in real time. Scrub through time to see the sky 10 years from now — or the day you were born. - PHOTO-REAL TEXTURES Saturn's rings, Jupiter's Great Red Spot, sunspots and solar granulation — every texture is generated on your device and stays crisp as you zoom. - CONTROL TIME From one second = hours, to one second = years. Watch the Moon change phase and the planets trace their orbits with your own eyes. - EXPLORE FREELY Pinch and swipe from outside the solar system down to a planet's face. Tap any body for details. - DESIGNED WITH RESPECT - No ads, ever - No in-app purchases — one simple price - Works fully offline, on a plane or on a mountain - Collects zero personal data For curious kids asking "why?" For stargazers who want a quiet moment of awe. The real universe, in your pocket. LANGUAGES English, Japanese, Simplified Chinese, Korean, Spanish, French, German

Screenshots

Planet4 screens
COSMOS4 screens

Verdict

The call

The clearest difference is iOS requirement: COSMOS at 15.0 against Planet's 17.0. On price, update cadence, ads 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

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

Planet ships an update weekly, COSMOS every 2 weeks. The most recent releases landed on October 20, 2026 and October 25, 2026 respectively.

Scorecard1 real difference · 8 level
Planet versus COSMOS: the parameters behind the verdict, then further details
ParameterPlanetCOSMOS
PriceFreeFree
Rating—5.0 (3 ratings) — better
Number of ratings—3 — better
Update frequencyWeekly — betterEvery 2 weeks
AdsNoNo
In-app purchasesNoNo
Monetization—Paid
DevicesiPhone, iPadiPhone, iPod
Requires iOS17.015.0 — better
Further details — not scored
Size25 MB4 MB
Age rating9+4+
DeveloperAhmad khaled Samimyuudai tasaki

In-app purchases

None

Planet

No in-app purchases

None

COSMOS

No in-app purchases

Questions

Is Planet free?
Planet is free to download, with no in-app purchases.
Is COSMOS free?
COSMOS is free to download, with no in-app purchases.
Do Planet or COSMOS have ads?
Neither Planet nor COSMOS shows ads.
Which is updated more often, Planet or COSMOS?
Planet ships an update weekly, and COSMOS every 2 weeks. Most recently, Planet was updated on October 20, 2026 and COSMOS on October 25, 2026.

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