Comparison

By vs Planet

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

Head to head
About

By

Features
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The Physics of Stars β€” in your hand. By-Pass is an interactive physics laboratory that brings the fascinating complexity of Newtonian mechanics to your iPad and iPhone. Here, you become the architect of orbital systems and watch simple forces give rise to highly complex mathematical patterns. Unlike simple animations, By-Pass uses its own physics engine with a simulation rate of 60 Hz to calculate real gravitational interactions accurately and without compromise. The physical core: Master of Orbits: Create satellites and planets with intuitive gestures. Use drag gestures to define the initial launch velocity and watch as objects settle into stable orbits or drift away into the vastness of outer space. Dynamic Gravitational Centers: Choose between 1, 2, or 3 suns. Experiment with the unstable and fascinating solutions of the famous three‑body problem. Each additional center dramatically alters the gravitational field and sends your planets onto unpredictable, dancing trajectories. Variable Gravitational Exponents: Switch between a fully realistic simulation (exponent 2.0) and modified fields for extremely long‑lasting, geometric path traces. Precision & Performance: Experience the simulation with a render target of 120 FPS. The physics runs independently at 60 Hz, ensuring smooth visuals even in the most complex systems. Procedural Matter: Each planet (Rocky, Lava, Gas, Ocean, Icy) is generated at runtime and behaves as a discrete physical entity within the simulation.

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 β€” or the Sun β€” 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 β€” 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 β€” 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 β€” 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.

Screenshots

By4 screens
Planet4 screens

Verdict

The call

The clearest difference is update cadence: By at daily against Planet's weekly. Planet's advantage is iOS requirement (17.0 vs 26.0). On price, ads, in-app purchases and device support there is nothing between them.

Scored on Price Β· Rating Β· Positive reviews Β· Number of ratings Β· Update frequency Β· Ads Β· In-app purchases Β· Monetization Β· Best chart rank Β· Devices Β· Requires iOS

CostPrice Β· In-app purchases Β· Ads Β· Monetization

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

UpkeepUpdate frequency

By ships an update daily, Planet weekly. The most recent releases landed on October 12, 2026 and October 3, 2026 respectively.

Scorecard2 real differences Β· 4 level
By versus Planet: the parameters behind the verdict, then further details
ParameterByPlanet
PriceFreeFree
Update frequencyDaily β€” betterWeekly
AdsNoNo
In-app purchasesNoNo
DevicesiPhone, iPadiPhone, iPad
Requires iOS26.017.0 β€” better
Further details β€” not scored
Size8 MB25 MB
Age rating4+9+
DeveloperAppno UG (haftungsbeschrankt)Ahmad khaled Samim

In-app purchases

None

By

No in-app purchases

None

Planet

No in-app purchases

Questions

Is By free?
By is free to download, with no in-app purchases.
Is Planet free?
Planet is free to download, with no in-app purchases.
Do By or Planet have ads?
Neither By nor Planet shows ads.
Which is updated more often, By or Planet?
By ships an update daily, and Planet weekly. Most recently, By was updated on October 12, 2026 and Planet on October 3, 2026.

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