Comparison

Number Line, by MLC vs Sumdog

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

Head to head
About

Number Line, by MLC

This app allows students to visualize number sequences and demonstrate mathematical strategies. It supports various number types and offers tools for annotation, problem-solving, and sharing work. Ideal for elementary classrooms and iPad learning environments.

Highlights
  • Visualize number sequences
  • Demonstrate counting, adding, subtracting, multiplying, dividing
  • Use whole numbers, fractions, decimals, or negative numbers
  • Add custom tick marks and labels
  • Hide and reveal numbers and jumps
  • Annotation and drawing tools
  • Save and share work
Features
Read full description

Number Line helps students visualize number sequences and demonstrate strategies for counting, comparing, adding, subtracting, multiplying, and dividing. Choose number lines labelled with whole numbers, fractions, decimals, or negative numbers. Or use a blank number line, with or without tick marks. Describe intervals between points on the line using forward or backward jumps above and below the line. Jumps can be labelled with their values or left blank. Add custom tick marks to the number line to show equivalence or compare number values. Show strategies with drawing and annotation tools. Hide elements of the sequence shown on the number line, which challenges students to use what they know about number relationships and computation to identify those missing elements. This virtual number line is an open-ended educational tool, ideal for elementary classrooms and other learning environments that use iPads. For more Number Line resources and other apps, visit: www.mathlearningcenter.org/apps FEATURES • Mark the number line with multiples of whole numbers, fractions, or decimals. In addition, set the starting value of the line, including using negative values. • Add and manipulate forward and backward jumps, above or below the line. • Label jump bars, manually or automatically, to show intervals or hide labels altogether. • Add custom tick marks and values to blank number lines. • Hide and reveal numbers on the number line. • Hide and reveal jumps, numbers, and other elements with resizable covers to create your own problems and model strategies. • Use the drawing tools to annotate work and show understanding. • Add equations, expressions, and descriptions with the math text and writing tools. • Share your work by saving an image or providing a share code to others. MORE APPS For more Number Line resources and other apps, visit: www.mathlearningcenter.org/apps LEARN MORE To learn about Bridges in Mathematics, an elementary curriculum that employs visual models like number line, visit: www.mathlearningcenter.org/bridges/overview ABOUT US This resource is brought to you by The Math Learning Center, a nonprofit organization dedicated to K-12 education since 1976. ACKNOWLEDGEMENTS This app was crafted by Clarity Innovations. We help improve teaching and learning by creating solutions that match promising technologies with the needs of education. Visit us: www.clarity-innovations.com

About

Sumdog

This app offers personalized math and spelling practice for children aged 5-14 through engaging games and adaptive learning. It uses diagnostic tests to tailor learning journeys and provides virtual rewards to motivate students. Parents can set up accounts for home use or connect to school-assigned work.

Highlights
  • Personalized adaptive learning
  • Engaging single and multiplayer games
  • Thousands of standards-aligned questions
  • Virtual coin rewards system
  • 3D avatar and house personalization
  • Diagnostic assessment
Features
Read full description

Make learning fun with Sumdog! Sumdog delivers highly engaging personalized practice for math and spelling, both in-school and at home. Suitable for children aged 5-14, our adaptive learning games and online rewards motivate children to learn and encourages regular practice. When children first use Sumdog, we run a short diagnostic test to provide a snapshot of their learning and areas for development. Our adaptive learning engine then uses the outcomes of the diagnostic to ensure each child’s starting point on Sumdog is at the right level. From this point, our sophisticated adaptive algorithms create a personalized learning journey based for each child based on their progress. - Over 30 engaging single and multiplayer games - Thousands of standards-aligned questions designed to consolidate and extend in-class learning - Virtual coin rewards to motivate children to learn - A 3D avatar, house and garden for children to personalize “I never thought an online program could do so much in such short bursts of time.” D. Hendershot, West Elementary, Kansas, US. Account set-up If your child has an account from school: Your child can log in with their details from their school. They’ll then be able to access any work that has been set by their teachers. If your child does not have an account from school: In the Sumdog app, parents can purchase a family plan covering up to 3 children. Once you’ve done this, you’ll create logins for your child to use the app. This gives them access to Sumdog’s games, and thousands of math, spelling and grammar questions. Subscription details: Your subscription starts with a free trial period and then changes to a subscription from $8.99 per month. No commitment period. Download the app and get started today! The amount will be deducted automatically every month via your Apple account. As long as the "Automatic renewal" feature is not disabled via the Apple account settings on your device, the subscription will automatically renew every month no later than 24 hours before your subscription period expires. Sumdog Terms: https://learn.sumdog.com/en-us/about-us/terms-of-use Sumdog Privacy: https://learn.sumdog.com/en-us/about-us/privacy-policy

Screenshots

Sumdog4 screens

Verdict

The call

The clearest difference is in-app purchases: Number Line, by MLC at none against Sumdog's 1. Number Line, by MLC also leads on rating (4.4 vs 4.2). Sumdog's advantage is update cadence (every 2 months vs every 13 months) and ratings volume (1.6K vs 15). On price, review sentiment, ads 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

Both are free to download. Sumdog sells 1 in-app purchase, starting at $8.99 per month. Number Line, by MLC asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Number Line, by MLC holds the better App Store score, 4.4 against 4.2. That said, the two scores are not equally well evidenced: Sumdog has 1.6K ratings behind it against 15, so its average is the more settled of the two. Written reviews point the same way: 67% of Number Line, by MLC's written reviews are positive against 64% of Sumdog's.

UpkeepUpdate frequency

Number Line, by MLC ships an update every 13 months, Sumdog every 2 months. Both last shipped on November 6, 2026.

Scorecard6 real differences · 4 level
Number Line, by MLC versus Sumdog: the parameters behind the verdict, then further details
ParameterNumber Line, by MLCSumdog
PriceFreeFree
Rating4.4 (15 ratings) — better4.2 (1.6K ratings)
Positive reviews66.7% of reviews — better63.7% of reviews
Number of ratings151.6K — better
Update frequencyEvery 13 monthsEvery 2 months — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPadiPhone, iPad, iPod — better
Requires iOS16.115.0 — better
Further details — not scored
Size7 MB135 MB
Age rating4+4+
DeveloperThe Math Learning CenterSumdog Ltd.

Customer experience

Number Line, by MLC

All ratings15 ratings
Positive86.7%
Neutral0.0%
Negative13.3%
Written reviews12 reviews
Positive66.7%
Neutral16.7%
Negative16.7%

Sumdog

All ratings1,556 ratings
Positive78.3%
Neutral4.9%
Negative16.8%
Written reviews361 reviews
Positive63.7%
Neutral10.5%
Negative25.8%

Bugs and requests

Number Line, by MLC

Not enough reviews yet to summarise bugs or requests.

Sumdog

Reported bugs

4 issues
  • Flower Defenders game not working properly
  • Goalz game not registering shots correctly
  • Sudden logout issues
  • Incompatibility with certain devices or browsers

Requested features

5 requests
  • Add more free games
  • Bring back old 2D games
  • Allow interaction with house and garden items
  • Improve multiplayer functionality
  • Add more customization options for avatar and house

In-app purchases

None

Number Line, by MLC

No in-app purchases

1 purchases

Sumdog

Subscriptions1
  • Family Membership7 Days trial$8.991 Month

Questions

Is Number Line, by MLC free?
Number Line, by MLC is free to download, with no in-app purchases.
Is Sumdog free?
Sumdog is free to download, with in-app purchases available.
Which has better reviews, Number Line, by MLC or Sumdog?
Number Line, by MLC is rated higher. Number Line, by MLC averages 4.4 out of 5 from 15 ratings, while Sumdog averages 4.2 from 1.6K ratings.
Do Number Line, by MLC or Sumdog have ads?
Neither Number Line, by MLC nor Sumdog shows ads.
Which is updated more often, Number Line, by MLC or Sumdog?
Number Line, by MLC ships an update every 13 months, and Sumdog every 2 months. Most recently, Number Line, by MLC was updated on November 6, 2026 and Sumdog on November 6, 2026.

Other comparisons