Comparison

Kalley's Machine Plus Cats vs Snap Science

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

Head to head
About

Kalley's Machine Plus Cats

An interactive storybook where a child's imaginative drawing of a machine comes to life. Explore playful interactions, help the machine perform various actions, and engage with whimsical cats. Features include read-to-me and touch-to-read options for young readers.

Highlights
  • Interactive machine play
  • Smash, inflate, shrink, and mold objects
  • Interact with cats
  • Read-to-me narration
  • Touch-to-read word highlighting
  • Child-friendly controls
Features
Read full description

Based on a true story of childhood optimism, Kalley’s Machine Plus Cats is the super-fun interactive story about a 4-year-old girl’s drawing and her heartwarming plan to save her dad from his daily commute. PRESS ----------------------------------------------- USA Today (4/4 Stars) : “This app showcases some of the most elegant interactions ever placed inside of a kids’ book app.” Common Sense Media (5/5 Stars) : “Kalley’s excitement about her cool machine is contagious.” 148 Apps (4.5/5 Stars) : “I am so very impressed with the wonderful and witty machines ... as well as the overall quality of this app.” The iMums (5/5 Stars) : “A beautiful and brilliant storybook app unlike any I have ever seen.” AWARDS & HONORS ---------------------------- * USA Today’s 10 TOP KIDS APPS of 2014 * Kirkus’ BEST BOOK APPS of 2014 * 2014 Cybils AWARD WINNER * Common Sense Media's Best Book Apps for Kids * TechWithKids BEST PICK APP * THE KIRKUS STAR - Awarded to Books of Exceptional Merit * mFWA Mobile of the Day - for Interactive Experience STORY ---------------------------------------------- When Kalley shows her dad her drawing for a new machine, he is baffled by the confusing collection of hammers, gears, fire, smoke and conveyors. As Kalley explains each part of her invention, the drawing comes to life even as its overall purpose becomes less and less clear to her dad. It is only when Kalley explains the machine’s final component that her master plan to keep her dad from commuting is revealed. THE STORY BEHIND THE STORY --------- So, there really is a ‘Kalley’. She really drew a machine. Her dad couldn’t build it. So they made an app out of it instead. Full story at kalleysmachine.com. FEATURES ---------------------------------------- ► PLAY WITH MACHINES! Kalley’s Machine was crafted with interactivity as the first priority. Satisfyingly touchable controls put kids in charge of each twist and smash of the machine. Controls come in a wide machiney variety: ● Cranks ● Sliders ● Dials ● Levers ● Switches ● Buttons With the machine, kids can: ● Smash Stuff ● Inflate Stuff ● Shrink Stuff ● Burn Stuff (or lightly toast it) ● Paint Stuff ● Grab Stuff ● Drop Stuff ● Mold Stuff Into Shapes ● Do A Few Other Things Including... ► MESS WITH CATS! Kalley’s Machine is a story based on a 4 year-old girl’s drawing. As such, it includes cats. They are completely irrelevant to the story. However, they are way fun to harass. Tease them. Scare them. Puzzle them. Adore them. We think you’ll love the cats. ► GET YOUR READ ON! Cuz it’s a story, right? Of course, you can read the story the old-fashioned way. But, to aid new readers, we’ve also included two helpful interactive story features: ● Read-to-Me, narrated by Kalley and her dad with highlighted words. ● Touch-to-Read, where words are spoken when they are touched. ► TRY TO LEARN! Honestly, we designed this story to be fun. But if you're not careful, you might actually learn something too! The interactive medium offers kids great chances to explore some basic concepts which are both safer and less messy than their real-world alternatives. Creative parents may recognize the opportunity to discuss: ● Subtractive Color Mixing ● Pressure/Temperature Relationships ● Gear Ratios ● Air Pressure/Vacuums ● How Overcooking Can Burn Stuff ► KEEP KIDS SAFE! We have made this app super-safe for kids by having: ● No Ads ● No In-App-Purchases ● Parental Gates in Our Parents Section

About

Snap Science

This app uses an AI-powered science buddy to answer children's questions and identify objects from photos. It encourages daily curiosity with fun facts and is built by science education experts.

Highlights
  • AI science buddy answers questions
  • Identify objects from photos
  • Safe, kid-friendly AI
  • Encourage daily curiosity
  • Built by science education experts
Features
Read full description

Meet Haley, your child’s friendly science buddy! Haley is a curious, talkative science expert who loves exploring the world and sharing fun facts. By harnessing advanced AI—safely trained with our trusted science knowledge—Haley gives quick, kid-friendly answers whenever your child asks a question or snaps a picture of something intriguing. Key Features: •Ask Anything, Anytime: Your child can tap, ask a question, and Chip will respond with a short, clear explanation just right for their age. •Snap a Photo, Discover More: From insects to leaves, Chip identifies and explains what’s in the picture, turning everyday moments into exciting science discoveries. •Safe, Kid-Friendly AI: Our AI is trained on reliable scientific information and designed with safeguards that put your family’s privacy first. No personal info leaves the device, ever. •Encourage Daily Curiosity: Ask questions each day, earn streaks, and keep that inquisitive spark glowing—Chip’s got fresh, lesser-known facts ready to amaze. •Built by Science Education Experts: From the creators of the #1 science app for kids, Chip builds on years of kid-tested teaching to inspire confidence, wonder, and a love of learning. Your child deserves a safe place to ask big questions and get bright, welcoming answers. Download now and let Chip transform their curiosity into a joyful adventure—one simple question at a time! Privacy Policy: https://www.stemschool.tappityapp.com/ask-chip-privacy-policy Terms: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Kalley's Machine Plus Cats4 screens
Snap Science4 screens

Verdict

The call

The clearest difference is in-app purchases: Kalley's Machine Plus Cats at none against Snap Science's 1. Kalley's Machine Plus Cats also leads on ratings volume (38 vs 3) and iOS requirement (11.0 vs 17.6). Snap Science's advantage is rating (5.0 vs 4.7) and update cadence (every 10 days vs every 5 weeks). On price, review sentiment, 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. Snap Science sells 1 in-app purchase, starting at $3.99 per month. Kalley's Machine Plus Cats asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Snap Science holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: Kalley's Machine Plus Cats has 38 ratings behind it against 3, so its average is the more settled of the two. Written reviews point the same way: 93% of Kalley's Machine Plus Cats's written reviews are positive against 100% of Snap Science's.

UpkeepUpdate frequency

Kalley's Machine Plus Cats ships an update every 5 weeks, Snap Science every 10 days. Both last shipped on October 24, 2026.

Scorecard6 real differences · 4 level
Kalley's Machine Plus Cats versus Snap Science: the parameters behind the verdict, then further details
ParameterKalley's Machine Plus CatsSnap Science
PriceFreeFree
Rating4.7 (38 ratings)5.0 (3 ratings) — better
Positive reviews92.5% of reviews100.0% of reviews — better
Number of ratings38 — better3
Update frequencyEvery 5 weeksEvery 10 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaidFree with in-app purchases — better
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS11.0 — better17.6
Further details — not scored
Size35 MB29 MB
Age rating4+4+
DeveloperRocketWagon, LLCTappity, Inc.

Customer experience

Kalley's Machine Plus Cats

All ratings37 ratings
Positive91.9%
Neutral0.0%
Negative8.1%
Written reviews67 reviews
Positive92.5%
Neutral3.0%
Negative4.5%

Snap Science

All ratings3 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Bugs and requests

Kalley's Machine Plus Cats

Reported bugs

3 issues
  • Cannot get past the first page
  • No sound at all
  • Navigation issues on older devices

Requested features

5 requests
  • Disable swipe feature
  • More interactive elements on the last page
  • More content/sequels/series
  • More interaction with cats
  • More interactive elements in general

Snap Science

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

Kalley's Machine Plus Cats

No in-app purchases

1 purchases

Snap Science

Subscriptions1
  • Explorer Membership$3.991 Month

Questions

Is Kalley's Machine Plus Cats free?
Kalley's Machine Plus Cats is free to download, with no in-app purchases.
Is Snap Science free?
Snap Science is free to download, with in-app purchases available.
Which has better reviews, Kalley's Machine Plus Cats or Snap Science?
Snap Science is rated higher. Kalley's Machine Plus Cats averages 4.7 out of 5 from 38 ratings, while Snap Science averages 5.0 from 3 ratings.
Do Kalley's Machine Plus Cats or Snap Science have ads?
Neither Kalley's Machine Plus Cats nor Snap Science shows ads.
Which is updated more often, Kalley's Machine Plus Cats or Snap Science?
Kalley's Machine Plus Cats ships an update every 5 weeks, and Snap Science every 10 days. Most recently, Kalley's Machine Plus Cats was updated on October 24, 2026 and Snap Science on October 24, 2026.

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