Comparison

Portable Planetarium vs GowanusAR

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

Head to head
About

Portable Planetarium

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The planetarium is based on the HIP (Hipparcos star chart) and displays stars of 5th magnitude or higher (1465 stars), names of famous stars, and lines and names of constellations. The movements of the planets are also reproduced and lines are drawn on the trajectories of their movements. When the application is launched, an earth model is placed 50 centimeters in front of the device, based on the device's position. A celestial sphere with a radius of 200 cm is placed based on the earth model, and stars and planets are placed on the celestial sphere. The radius of the celestial sphere can be zoomed in and out. You can also view the celestial sphere from inside or outside. # Features - [x] ARKit reproduces a planetarium. - [x] The planetarium is based on the HIP (Hipparcos star chart). - [x] Displays stars (magnitude 5 or higher, 1465 stars). - [x] Famous stars are labeled with their names. - [x] Displays constellation lines and names on the celestial sphere. - [x] Draws azimuth lines on the celestial sphere. - [x] Displays the sun, moon, and five planets (Mercury, Venus, Mars, Jupiter, and Saturn) and draws lines on their trajectories. - [x] The Earth model is placed in the center of the celestial sphere with a realistic tesure. - [x] The positions of the planets are calculated (using the Horizons API) based on actual values. - [x] Observation locations can be changed (11 locations). - [x] Date of observation can be changed (2024-2028). - [x] Time can be increased or decreased with the tap of a button. You can also advance the time automatically. - [x] Speed adjustment function (minus value for reverse rotation) to adjust the movement of the celestial sphere. - [x] Zoom function (zoom in/out) to change the size of the celestial sphere. - [x] Toggle to show/hide text information and coordinate axes. - [x] Drag the earth model to move the position of the celestial sphere. - [x] Change the background color by identifying day and night. ## How to use 1. when you launch the application, you will be asked for "permission to use camera" at first launch. If you allow it, an ARKit session will start. 2. The earth model and coordinate axes are placed 100 cm in front of the device, based on the device's position. 3. Tap the "Load Stars" button to load the star and planet models. Please wait a moment. 4. After loading, the stars, planets and constellation lines are drawn on the celestial sphere. 5. By moving the device, the celestial sphere (planetarium) can be observed from various angles and positions. 6. Tap the buttons at the bottom of the screen to adjust speed and zoom. 7. You can change the observation point from the menu in the upper right corner of the screen. 1. Tokyo (Japan) 2. Greenwich (England) 3. Dakar (Senegal) 4. Cairo (Egypt) 5. cape town (South Africa) 6. Melbourne (Australia) 7. Wellington (New Zealand) 8. Honolulu (USA) 9. Los Angeles (USA) 10. Vancouver (Canada) 11. Buenos Aires (Argentina) 8. Observation dates can be changed from the Set Date button. (2024 - 2028) 9. You can show/hide text information and coordinate axes from the menu in the upper right corner of the screen.

About

GowanusAR

Experience the history of Brooklyn's Gowanus Canal through an immersive augmented reality application. Discover stories, sounds, and speculative futures embedded in the landscape as you explore the neighborhood.

Highlights
  • Augmented Reality Navigation
  • Immersive Spatial Audio
  • Interactive Storytelling
  • Speculative Histories
  • Location-based AR experiences
Features
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GowanusAR is an immersive augmented reality (AR) experience that brings the layered histories of Brooklyn’s Gowanus Canal to life. Walk the streets and uncover voices, stories, and sounds embedded in the land. In our debut scene, you’ll encounter speculative futures, industrial pasts, and sonic portals, all triggered by your location. Features: Augmented Reality Navigation: Explore a site-specific scene designed to unfold as you move through the Gowanus neighborhood. Immersive Audio: Spatial soundscapes respond to your position, layering narration, ambiance, and historical textures. Interactive Storytelling: Engage with dynamic AR elements that reveal hidden aspects of Gowanus’ environmental and cultural evolution. Speculative Histories: Encounter narrative fragments that blur the boundaries between past, present, and possible futures. This is just the beginning. More scenes and voices will be released soon. Headphones recommended. Location access required.

Screenshots

Portable Planetarium4 screens
GowanusAR4 screens

Verdict

The call

The clearest difference is iOS requirement: GowanusAR at 13.0 against Portable Planetarium's 16.0. 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

Portable Planetarium ships an update every 4 months, GowanusAR every 5 months. The most recent releases landed on October 3, 2026 and October 6, 2026 respectively.

Scorecard1 real difference · 8 level
Portable Planetarium versus GowanusAR: the parameters behind the verdict, then further details
ParameterPortable PlanetariumGowanusAR
PriceFreeFree
Rating—5.0 (1 ratings) — better
Number of ratings—1 — better
Update frequencyEvery 4 months — betterEvery 5 months
AdsNoNo
In-app purchasesNoNo
Monetization—Free
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS16.013.0 — better
Further details — not scored
Size85 MB1.2 GB
Age rating4+4+
DeveloperMasaya NagaokaSarah Drury

In-app purchases

None

Portable Planetarium

No in-app purchases

None

GowanusAR

No in-app purchases

Questions

Is Portable Planetarium free?
Portable Planetarium is free to download, with no in-app purchases.
Is GowanusAR free?
GowanusAR is free to download, with no in-app purchases.
Do Portable Planetarium or GowanusAR have ads?
Neither Portable Planetarium nor GowanusAR shows ads.
Which is updated more often, Portable Planetarium or GowanusAR?
Portable Planetarium ships an update every 4 months, and GowanusAR every 5 months. Most recently, Portable Planetarium was updated on October 3, 2026 and GowanusAR on October 6, 2026.

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