Comparison

HMH Science Dimensions vs Merge Explorer

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

Head to head
About

HMH Science Dimensions

This augmented reality app transforms book covers into interactive science experiments. Students can scan their textbooks to launch 3D models and explore concepts like weather, solar energy, and the solar system. It's designed to make learning engaging and fun for young students.

Highlights
  • Augmented reality science experiments
  • Scan book covers to activate content
  • Interactive 3D models
  • Explores various science topics
  • Engaging learning experience
  • Group or pair work friendly
Features
Read full description

HMH Science Dimensions AR! (In order to access this app’s content, you will need any Student Edition book cover from HMH’s California Science Dimensions AR program). HMH Science Dimensions AR is an augmented reality tool that turns your students’ book cover into a fun, unique learning experience. To play, open the app and scan the Student Activity Book cover from any grade using a smartphone or tablet. Then watch an augmented reality experiment pop right out of it! HMH Science Dimensions AR gets students out of their seats and thinking about the science they’ll be learning in the coming year. It can also serve as a short, fun homework activity. For target images please go to: https://prod-hmhco-vmg-craftcms-private.s3.amazonaws.com/documents/CA_SD_AR_Covers.pdf Experiments and investigations include… Weather Materials Solar Energy Food Chains Biological Systems Photosynthesis The Solar System Sound Waves How Crystals Form Tips Move your device around the cover and even move the cover itself to get the full experience. The experiments lend themselves well to students working in small groups or pairs. App Info This app does not collect any personally identifiable information. This app contains no social media sharing or links to websites. This app does not track the user’s location. For users age 6 or younger, we recommend child-safe device covers. Avoid pressing buttons or controls outside the main screen area when holding the device as doing so may minimize or close the game.

About

Merge Explorer

Explore over 100 interactive science simulations using a smartphone and a Merge Cube. Investigate volcanoes, sharks, the solar system, and more with hands-on activities and quizzes. Ideal for K-8 students learning science at school or home.

Highlights
  • Over 100 science simulations
  • Interactive Merge Cube experiences
  • Hands-on learning activities
  • Built-in quizzes
  • NGSS-aligned K-8 curriculum
  • Physical, Life, and Earth/Space Science topics
Features
Read full description

PLEASE NOTE: This app requires a Merge Cube and a smartphone or a tablet to experience. Find out how to get a Merge Cube and learn more at: https://www.MergeCube.com. Students can learn science effectively with over 100 science simulations they can touch, hold and interact with! Merge Explorer (along with a Merge Cube) allows students to investigate a smoking volcano in the palm of their hand, examine a great white shark up close, hold and explore the solar system, dissect a frog (humanely!), and so much more. With easy-to-follow activities and built-in quizzes, students gain key knowledge while immersed in learning, both in the classroom or while remote learning at home. Merge Explorer includes NGSS-aligned topics for K-8th grade, like Physical Science, Life Science, and Earth & Space Science. If you have any questions or suggestions, we want to hear from you! Contact us at any time at support@mergeedu.com. Privacy Policy: https://MergeEdu.com/privacy-policy Terms of Use: https://MergeEdu.com/terms-of-use

Screenshots

HMH Science Dimensions4 screens
Merge Explorer4 screens

Verdict

The call

The clearest difference is rating: Merge Explorer at 4.1 against HMH Science Dimensions's 2.3. Merge Explorer also leads on review sentiment (46% vs 25%) and ratings volume (279 vs 17). HMH Science Dimensions's advantage is in-app purchases (none vs 4) and iOS requirement (9.0 vs 15.0). On price, update cadence, ads and device support 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. Merge Explorer sells 4 in-app purchases, starting at $9.99 per month. HMH Science Dimensions asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Merge Explorer holds the better App Store score, 4.1 against 2.3. That said, the two scores are not equally well evidenced: Merge Explorer has 279 ratings behind it against 17, so its average is the more settled of the two. Written reviews point the same way: 25% of HMH Science Dimensions's written reviews are positive against 46% of Merge Explorer's.

UpkeepUpdate frequency

HMH Science Dimensions ships an update every 2 months, Merge Explorer monthly. The most recent releases landed on October 21, 2026 and October 23, 2026 respectively.

Scorecard6 real differences · 4 level
HMH Science Dimensions versus Merge Explorer: the parameters behind the verdict, then further details
ParameterHMH Science DimensionsMerge Explorer
PriceFreeFree
Rating2.3 (17 ratings)4.1 (279 ratings) — better
Positive reviews25.0% of reviews46.2% of reviews — better
Number of ratings17279 — better
Update frequencyEvery 2 monthsMonthly — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS9.0 — better15.0
Further details — not scored
Size227 MB1.3 GB
Age rating4+4+
DeveloperHoughton Mifflin HarcourtMerge Apps

Customer experience

HMH Science Dimensions

All ratings16 ratings
Positive31.3%
Neutral6.3%
Negative62.5%
Written reviews4 reviews
Positive25.0%
Neutral0.0%
Negative75.0%

Merge Explorer

All ratings279 ratings
Positive76.3%
Neutral7.2%
Negative16.5%
Written reviews65 reviews
Positive46.2%
Neutral10.8%
Negative43.1%

Bugs and requests

HMH Science Dimensions

Not enough reviews yet to summarise bugs or requests.

Merge Explorer

Reported bugs

13 issues
  • App crashes on iPad
  • App crashes when pressing play
  • Camera not working in app
  • Black screen when using cube or camera
  • VR function broken
Show 8 more
  • VR doesn't work with iPhone XS Max
  • App crashes or loads forever
  • Problems with galactic explore
  • App has trouble recognizing the cube
  • Screen recording only records cube, not overlay
  • Words appear sideways in horizontal mode
  • Content appears incorrectly
  • App crashes

Requested features

9 requests
  • Make the app free to play
  • Add more fun things, not just learning
  • Bring back the fun apps (time bomb, block courses)
  • Allow users to create their own games for the merge cube
  • Add a way to reset quizzes for class sets of devices
Show 4 more
  • Improve functionality for remote teaching, including screen recording
  • Add more content in the future
  • Add dark mode option
  • Add advanced analytics dashboard

In-app purchases

None

HMH Science Dimensions

No in-app purchases

4 purchases

Merge Explorer

Subscriptions4
  • Merge EDU Individual14 Days trial$9.991 Month
  • Explorer Premium Monthly14 Days trial$9.991 Month
  • Merge EDU Individual14 Days trial$99.991 Year
Show 1 more
  • Explorer Premium Annual14 Days trial$99.991 Year

Questions

Is HMH Science Dimensions free?
HMH Science Dimensions is free to download, with no in-app purchases.
Is Merge Explorer free?
Merge Explorer is free to download, with in-app purchases available.
Which has better reviews, HMH Science Dimensions or Merge Explorer?
Merge Explorer is rated higher. HMH Science Dimensions averages 2.3 out of 5 from 17 ratings, while Merge Explorer averages 4.1 from 279 ratings.
Do HMH Science Dimensions or Merge Explorer have ads?
Neither HMH Science Dimensions nor Merge Explorer shows ads.
Which is updated more often, HMH Science Dimensions or Merge Explorer?
HMH Science Dimensions ships an update every 2 months, and Merge Explorer monthly. Most recently, HMH Science Dimensions was updated on October 21, 2026 and Merge Explorer on October 23, 2026.

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