Comparison

StarTracker HD vs Urinary System Quiz

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

Head to head
About

StarTracker HD

Explore the night sky with this augmented reality planetarium. Identify stars, constellations, planets, and deep sky objects by simply pointing your device at the sky. All data is available offline.

Highlights
  • Augmented Reality Star Gazing
  • Identify 8000+ stars, planets, and constellations
  • Offline data access
  • Search and lock celestial objects
  • Time Machine feature
  • High-quality graphics
Features
Read full description

== Best StarGazing experience @60fps! == == Video: http://tiny.cc/starvideo == --- Top 1 Education app in 34 countries and Top 10 Education app in 79 countries when FREE! Thank you all my dear users, please leave a review or rating if you love this application! --- Hey, get outdoor with your friends and start star gazing! Let StarTracker guide you to explore the universe. Just hold up and point the device to the sky and have fun! You can see any stars, constellations and deep sky objects you are watching in reality. ======================== What our user said: "Best star gazing app I've ever used. Very well put together and great visuals!!! From end to end this app is a must-have for anyone interested in astronomy!!" "This app is a marvel of technology, art, and science. Super smooth operation, great graphics and a great merging of the devices capabilities. Having grown up using star charts and compasses, this app feels like science fiction come to life. Great job!" "Looking at the sky was never this incredible!" "If you download only one app, make sure it's this one!! This is one of the best apps I've ever seen, period! Its quality is unmatched among star gazing apps!" ======================== Features: • Augmented Reality Star Gazing with gyroscope! Just hold up the device. • Sun, Moon, planets and 8000+ stars visible to the naked eyes. • 88 Constellations & 100+ deep sky objects with magnificent graphics. • All data is offline! • Search and Lock the objects in Solar system, 12 Zodiac Constellations, 88 Constellations, Deep Sky Objects and Famous Stars. • 3D compass in AR mode, indicate position of objects your searched. • Location auto set by GPS, or set manually. • Time Machine. Time and date can be adjusted smoothly. • Capture a screenshot and share with your friends on Facebook, Twitter or save to Photos. • Smooth motion flow and quick response which is realized by cutting edge signal processing technique. • Superb high quality graphics with full screen anti-aliasing. Usage: • Bottom Right: Hide/Show Main Setting Menu, settings for name display, constellation, deep sky object, night mode, star amount and grid mode. • Top Right: Search Menu (Solar system, 12 Zodiac and 88 Constellations, Deep Sky Object and Famous Stars) • Top Left: Location Menu, choose location from a world map. Below is the Share button. • Top bar: Time Machine Menu, adjust any time/date. • Bottom Left: AR Compass indicator in AR track mode, pan the screen to enter un-track mode and click track button to back. Tips: • When search any object under un-track mode, it will be locked at the center of the screen, then user can adjust time/date to see changes of the related sky. • When under un-track mode, just lift up the screen and point it to the sky to enter AR track mode.

About

Urinary System Quiz

Test your knowledge of the urinary system with over 300 quiz questions covering structure, function, and core concepts. Features three difficulty levels to aid in class preparation and grade improvement.

Highlights
  • Over 300 quiz questions
  • Covers structure and function
  • Includes excretion, renal circulation, nephron
  • Three difficulty levels
  • Helps prepare for class
  • Improves grades
Features
Read full description

Over 300 quiz questions on the Urinary System including structure, function, definitions, terms, core concepts including excretion, renal circulation, nephron, filtration, glomerular filtration rate and regulation. Glomerulus, proximal convoluted tubule nephron loop, collecting duct, water loss, countercurrent, renal function, hormone, and composition and properties of urine. 3 levels of quiz difficulty provide a great opportunity to quickly prepare for class ahead of time, learn more during lecture, and improve your grade. Check your learning, find holes in your knowledge, and provide an additional perspective on the subject with challenging questions for every level. If you can’t save study time, energy, and get your money’s worth from this Urinary System Quiz APP then it is time to switch majors.

Screenshots

Urinary System Quiz4 screens

Verdict

The call

The clearest difference is review sentiment: StarTracker HD at 59% against Urinary System Quiz's 0%. StarTracker HD also leads on rating (4.0 vs 1.0) and update cadence (every 5 months vs every 29 months). Urinary System Quiz's advantage is price ($1.99 vs $3.99) and device support (3 vs 1). On ads, in-app purchases, monetization model and iOS requirement 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

StarTracker HD costs $3.99 and Urinary System Quiz $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

StarTracker HD holds the better App Store score, 4.0 against 1.0. That said, the two scores are not equally well evidenced: StarTracker HD has 43 ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 59% of StarTracker HD's written reviews are positive against 0% of Urinary System Quiz's.

UpkeepUpdate frequency

StarTracker HD ships an update every 5 months, Urinary System Quiz every 29 months. The most recent releases landed on October 22, 2026 and October 29, 2026 respectively.

Scorecard6 real differences · 4 level
StarTracker HD versus Urinary System Quiz: the parameters behind the verdict, then further details
ParameterStarTracker HDUrinary System Quiz
Price$3.99$1.99 — better
Rating4.0 (43 ratings) — better1.0 (2 ratings)
Positive reviews59.4% of reviews — better0.0% of reviews
Number of ratings43 — better2
Update frequencyEvery 5 months — betterEvery 29 months
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPadiPhone, iPad, iPod — better
Requires iOS12.012.0
Further details — not scored
Size25 MB56 MB
Age rating4+4+
Developer身吉 潘Alpha Dog Marketing LLC

Customer experience

StarTracker HD

All ratings43 ratings
Positive74.4%
Neutral4.7%
Negative20.9%
Written reviews96 reviews
Positive59.4%
Neutral12.5%
Negative28.1%

Urinary System Quiz

All ratings2 ratings
Positive0.0%
Neutral0.0%
Negative100.0%
Written reviews3 reviews
Positive0.0%
Neutral0.0%
Negative100.0%

Bugs and requests

StarTracker HD

Reported bugs

15 issues
  • App crashes on startup or during use
  • Compass direction incorrect (north pointing wrong direction)
  • Gyroscope not responding or locked
  • Share button causes crashes
  • Forward/share button greying out and causing screen loss
Show 10 more
  • Screen display only showing bottom right corner on iPad Pro 12.9
  • App spinning continuously without stopping
  • Screen orientation lock issues after iOS updates
  • Duplicate app installations appearing
  • iPad 2 compatibility issues despite gyroscope presence
  • Inaccurate celestial object positioning (e.g., M71 placement)
  • Sun position showing incorrectly during daytime
  • Ursa Minor not rotating properly over 24-hour period
  • Menu disappearing after using forward button
  • Half-screen display stuck after exploring tools

Requested features

13 requests
  • Add search functionality for celestial objects
  • Include ISS and satellite tracking
  • Display object information (distance, magnitude, color, brightness)
  • Add ecliptic line visibility option
  • Show coordinate information (RA, Dec, Alt, Azimuth)
Show 8 more
  • Tap-to-identify popup descriptions for objects
  • Add grid markings and horizon line with directional labels
  • Better zoom control with more detailed object information
  • Ability to manually rotate and correct star map
  • Offline functionality without WiFi requirement
  • Remove or disable astrology content
  • Project capability for classroom screens
  • iPhone version availability

Urinary System Quiz

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

StarTracker HD

No in-app purchases

None

Urinary System Quiz

No in-app purchases

Questions

Is StarTracker HD free?
StarTracker HD costs $3.99, with no in-app purchases.
Is Urinary System Quiz free?
Urinary System Quiz costs $1.99, with no in-app purchases.
Which has better reviews, StarTracker HD or Urinary System Quiz?
StarTracker HD is rated higher. StarTracker HD averages 4.0 out of 5 from 43 ratings, while Urinary System Quiz averages 1.0 from 2 ratings.
Do StarTracker HD or Urinary System Quiz have ads?
Neither StarTracker HD nor Urinary System Quiz shows ads.
Which is updated more often, StarTracker HD or Urinary System Quiz?
StarTracker HD ships an update every 5 months, and Urinary System Quiz every 29 months. Most recently, StarTracker HD was updated on October 22, 2026 and Urinary System Quiz on October 29, 2026.

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