Comparison

Fraction as Slope vs Singularity by Vaonis

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

Head to head
About

Fraction as Slope

This app offers a visual approach to understanding fractions and slopes through interactive graphing. Students can manipulate lines on a grid to explore fraction equivalence, addition, subtraction, reduction, and expansion.

Highlights
  • Visual fraction and slope exploration
  • Add and subtract fractions visually
  • Compare fractions using slopes
  • Reduce and expand fractions
  • Explore fraction equivalence
Features
Read full description

Fraction as Slope helps students explore fractions and slope visually. The app shows how fractions can be understood as slopes of lines. Students can draw and move graphs of lines to explore, compare, add, subtract, reduce, and expand positive and negative fractions. This gives algebra students a visual way to build conceptual understanding of both fractions and slopes. Students can see equivalent fractions as lines with the same slope, compare fractions by comparing their slopes, and explore how changing a numerator or denominator changes the graph. Teachers With Apps: “Fraction as Slope by Esa Helttula of iDevBooks is simply elegant. It is written for big kids with a design that respects and lends gravity to what they are learning. The app is simply composed of an adjustable grid where numbers are plotted along an axis so that you can visually see a slope of that fraction with all its equivalents.” GeekDad: “Fraction as Slope allows your kids to play around with graphed lines and see the connection between fractions and slopes. It’s a straightforward, targeted learning app, and kids will enjoy manipulating the graphs manually.” Features: - Explore fractions as slopes of lines - Compare fractions visually using slopes - Add and subtract fractions with unlike denominators - Reduce and expand fractions visually - Explore equivalent fractions - Work with positive and negative fractions - Adjustable grid for open exploration Other iDevBooks Math Apps: Other iDevBooks math apps include Visual Multiplication Table, Visual Fractions Decimals Percentages, Decimal Rounding, Whole Number Rounding, Column Subtraction, Column Addition, Long Division, Long Multiplication, Lattice Multiplication, Fraction Math, Partial Differences Subtraction, Partial Quotients Division, Partial Sums Addition, and more. Feedback: New ideas to make this app better are welcome. Please visit idevbooks.com to give feedback. Privacy: This app has no ads, no in-app purchases, and does not transmit user data during operation. The app also does not contain links to other apps or to the web.

About

Singularity by Vaonis

Control your smart telescope to explore the cosmos. Discover celestial objects with personalized recommendations, capture stunning images of galaxies and nebulae, and share your astronomical journey.

Highlights
  • Automatic setup and alignment
  • Real-time image processing
  • Object catalog and coordinate pointing
  • Mosaic mode for wider views
  • Solar observation mode
  • Expert mode for advanced control
  • Night planning and automated exploration
Read full description

Singularity by Vaonis is the control center for your Stellina and Vespera observation stations. This intuitive mobile application allows you to explore the Cosmos with ease. Receive personalized recommendations on which objects to observe according to your geolocation and the astronomical calendar. Learn more about the history of the Universe and immortalize your trip by photographing galaxies, nebulae and star clusters. AUTOMATIC SETUP Just press the button, and let Stellina and Vespera do the rest. Your new companion will use your GPS to find its position on Earth, adjust its focus and be ready to take you anywhere you want in less than 5 minutes. AUTOMATIC ALIGNEMENT AND TRACKING Choose your destination in the Singularity object catalog or enter the celestial coordinates of the object. Your station will automatically point to the selected area, and track it to maintain optimal viewing conditions. IMAGE PROCESSING It only takes a few seconds for Stellina and Vespera to deliver the first image of your destination before compiling dozens, hundreds or even thousands of other images in real time, progressively revealing ever greater details and colors. SPACE CENTER Take control of your station from the Space Center: prepare your observation evening by checking the weather forecast, create and manage your observation locations, check the parameters of Stellina/Vespera... You can also read the astronomical news or our advice on Stellina and Vespera on our blog while waiting for nightfall. MOSAIC MODE CovalENS is the first automated “panorama mode” ever embedded into a telescope. This unique patented technology, developed by Vaonis, allows you to take several photos of a same stellar region and then automatically stitch them together, thus offering users a larger view (field) of the universe. SOLAR MODE Observe easily and safely the closest star to Earth during the day with the Vaonis solar filters. The Solar Mode allows you to observe and capture sunspots that show the intensity of the Sun’s activity. EXPERT MODE Access an unlimited number of objects with coordinate pointing. Customize your camera's exposure time and gain to generate initial files for manual processing using image editing software. PLAN MY NIGHT Program your observation station for the night and let it explore the Universe on its own. After a good night's sleep, recover your photos on a USB key (Stellina) or via Wi-FI FTP protocol (Vespera). SHARE YOUR JOURNEY ON SOCIAL NETWORKS Your trip is over, share it! Show the world your photos on social networks and join our community of explorers, using the hashtags #myStellina or #myVespera.

Screenshots

Singularity by Vaonis4 screens

Verdict

The call

The clearest difference is price: Singularity by Vaonis at Free against Fraction as Slope's $3.99. Singularity by Vaonis also leads on update cadence (every 5 weeks vs every 22 months) and ratings volume (74 vs 2). Fraction as Slope's advantage is rating (5.0 vs 4.1) and review sentiment (100% vs 64%). On 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

Singularity by Vaonis is free to download; Fraction as Slope costs $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Fraction as Slope holds the better App Store score, 5.0 against 4.1. That said, the two scores are not equally well evidenced: Singularity by Vaonis has 74 ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 100% of Fraction as Slope's written reviews are positive against 64% of Singularity by Vaonis's.

UpkeepUpdate frequency

Fraction as Slope ships an update every 22 months, Singularity by Vaonis every 5 weeks. The most recent releases landed on June 7, 2026 and October 14, 2026 respectively.

Scorecard8 real differences · 2 level
Fraction as Slope versus Singularity by Vaonis: the parameters behind the verdict, then further details
ParameterFraction as SlopeSingularity by Vaonis
Price$3.99Free — better
Rating5.0 (2 ratings) — better4.1 (74 ratings)
Positive reviews100.0% of reviews — better64.4% of reviews
Number of ratings274 — better
Update frequencyEvery 22 monthsEvery 5 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidFree — better
DevicesiPadiPhone, iPad, iPod — better
Requires iOS17.614.0 — better
Further details — not scored
Size1 MB401 MB
Age rating4+4+
DeveloperEsa HelttulaVaonis

Customer experience

Fraction as Slope

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Singularity by Vaonis

All ratings74 ratings
Positive77.0%
Neutral6.8%
Negative16.2%
Written reviews45 reviews
Positive64.4%
Neutral8.9%
Negative26.7%

In-app purchases

None

Fraction as Slope

No in-app purchases

None

Singularity by Vaonis

No in-app purchases

Questions

Is Fraction as Slope free?
Fraction as Slope costs $3.99, with no in-app purchases.
Is Singularity by Vaonis free?
Singularity by Vaonis is free to download, with no in-app purchases.
Which has better reviews, Fraction as Slope or Singularity by Vaonis?
Fraction as Slope is rated higher. Fraction as Slope averages 5.0 out of 5 from 2 ratings, while Singularity by Vaonis averages 4.1 from 74 ratings.
Do Fraction as Slope or Singularity by Vaonis have ads?
Neither Fraction as Slope nor Singularity by Vaonis shows ads.
Which is updated more often, Fraction as Slope or Singularity by Vaonis?
Fraction as Slope ships an update every 22 months, and Singularity by Vaonis every 5 weeks. Most recently, Fraction as Slope was updated on June 7, 2026 and Singularity by Vaonis on October 14, 2026.

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