Comparison

Project Planet Space vs CosmoMerge

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

Head to head
About

Project Planet Space

Explore our solar system with an interactive map. Discover planetary gravity, temperatures, and atmospheric data. Calculate your weight on other worlds and learn fascinating space facts.

Highlights
  • Interactive solar system map
  • Personalized weight and age calculations
  • Detailed planetary data widgets
  • Multi-language support
  • Metric/Imperial unit switching
  • Cosmic museum aesthetic
  • Real astronomical data integration
Features
Read full description

Project Planet - an interactive map of our solar system How much would you weigh on Jupiter? Why does a day on Mercury last longer than its year? Project Planet turns space facts into a fingertip-sized journey. Scroll through all nine planets (Pluto included), feel each world's pull on your own body, and explore the numbers astronomers have spent decades collecting. Highlights - Sticky scroll across the system: from Mercury to Pluto, each planet stays centred long enough for you to take it in. - You, on every world: enter your weight and age once and watch them recalculated by each planet's gravity and orbital period. - Five rich widgets per planet: surface temperature with reference markers (Antarctica, freezing, boiling), atmospheric pressure with composition chart, travel times from Earth from walking up to the speed of light, gravitational force with everyday objects (phone, backpack, car), and an interactive pressure simulator with phase changes for water, oxygen, CO2, hydrogen, nitrogen and mercury (Antoine equation under the hood). - Six languages: Czech, English, German, Slovak, Spanish and French, auto-detected from your device. - Metric or imperial: switch instantly; weights, temperatures and distances follow your preference. - Crafted to feel like a small cosmic museum: dark cosmic theme, hand-tuned typography, subtle scroll choreography, and a right rail that lets you jump to any planet. - Built on real data: gravitational accelerations, orbital periods, NASA mean temperatures, atmospheric compositions and substance phase transitions. Requires an internet connection. The app runs as a continuously updated webview and uses native iOS capabilities such as haptic feedback to add a tactile dimension to your interstellar journey.

About

CosmoMerge

Explore astronomy, geography, and history by merging tiles. Unlock knowledge and discover new entries in your atlas with each level you achieve. Enjoy a puzzle experience that educates and entertains.

Highlights
  • Merge tiles to unlock knowledge
  • Explore Solar System, Geography, and History
  • Atlas with descriptive entries
  • Undo and Revive gameplay options
  • Ad-free experience with purchase
Features
Read full description

CosmoMerge — Explore Space & Civilization Through Puzzle Astronomy, geography, and history. Merge tiles, unlock knowledge. 【Gameplay】 Swipe to merge identical tiles and climb from the lowest to the highest level. Each milestone unlocks an entry in the atlas with brief descriptions. 【Topics】 • Solar System: From Neptune to the Sun — discover planets and our star • Geography: Islands, mountains, rivers — explore Earth’s landscapes • History: Chinese dynasties from Xia to Qing — trace the flow of time 【Features】 • Undo: Take back a move when you slip • Revive: Get another chance when the game ends • Ad-free: One-time purchase to remove all non-item ads For puzzle lovers and curious minds.

Screenshots

Project Planet Space4 screens
CosmoMerge4 screens

Verdict

The call

The clearest difference is in-app purchases: Project Planet Space at none against CosmoMerge's 1. CosmoMerge's advantage is update cadence (every 2 days vs every 25 months). On price, rating, ratings volume and ads 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. CosmoMerge sells 1 one-off in-app purchase. Project Planet Space asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 5.0 for Project Planet Space against 5.0 for CosmoMerge. Both are backed by a comparable volume of ratings — 1 and 1 respectively.

UpkeepUpdate frequency

Project Planet Space ships an update every 25 months, CosmoMerge every 2 days. The most recent releases landed on November 4, 2026 and November 5, 2026 respectively.

Scorecard3 real differences · 6 level
Project Planet Space versus CosmoMerge: the parameters behind the verdict, then further details
ParameterProject Planet SpaceCosmoMerge
PriceFreeFree
Rating5.0 (1 ratings)5.0 (1 ratings)
Number of ratings11
Update frequencyEvery 25 monthsEvery 2 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.015.0
Further details — not scored
Size2 MB84 MB
Age rating4+4+
DeveloperMiroslav HanzelkaQingdao Chuyan Technology Co., Ltd

In-app purchases

None

Project Planet Space

No in-app purchases

1 purchases

CosmoMerge

One-time1
  • Remove Ads$1.99

Questions

Is Project Planet Space free?
Project Planet Space is free to download, with no in-app purchases.
Is CosmoMerge free?
CosmoMerge is free to download, with in-app purchases available.
Which has better reviews, Project Planet Space or CosmoMerge?
Project Planet Space and CosmoMerge are both rated 5.0 out of 5 on the App Store, from 1 and 1 ratings respectively.
Do Project Planet Space or CosmoMerge have ads?
Neither Project Planet Space nor CosmoMerge shows ads.
Which is updated more often, Project Planet Space or CosmoMerge?
Project Planet Space ships an update every 25 months, and CosmoMerge every 2 days. Most recently, Project Planet Space was updated on November 4, 2026 and CosmoMerge on November 5, 2026.

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