Comparison

Number Builder vs IEW Writing Toolbox

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

Head to head
About

Number Builder

This app helps solve math puzzles by calculating all possible equations from dice rolls and a target number. It supports basic arithmetic, powers, and roots, making it a useful tool for games like Number Knockout.

Highlights
  • Calculates all possible solutions
  • Supports basic arithmetic
  • Includes powers and roots
  • Input dice rolls and target number
  • Useful for Number Knockout game
Features
Read full description

Number Builder turns dice rolls into a hands-on way to practice mental math. SOLVE MODE Roll three dice, enter a target number, and see every way to combine your dice — using addition, subtraction, multiplication, division, exponents, and roots — to reach it. Great for checking your own work or discovering paths you hadn't thought of. CHALLENGE MODE Roll a set of dice and a target, then build the answer yourself — tapping dice and operators into place, left to right, with instant feedback when you're right. Six levels of difficulty take you from simple addition all the way up to exponents, fractional exponents, and roots, with targets up to 1,000. Challenge mode includes 3 free puzzles to try. After that, it unlocks with a single one-time purchase — no subscriptions, and Family Sharing means one purchase covers your whole family. BUILT FOR PRACTICE Six progressively harder levels, each changing exactly one thing about the challenge Customizable dice colors and styles Full support for larger text sizes and VoiceOver Solve mode stays completely free, no purchase required No data is collected. No ads, ever.

About

IEW Writing Toolbox

Features
Currently charting
Read full description

IEW Writing Toolbox app is the perfect tool for IEW students and teachers! It includes the IEW structural models and stylistic techniques, clearly explained and easy to apply. The search for a word features a focused thesaurus, helping you find -ly adverbs, strong verbs, and quality adjectives to enhance any composition. This toolbox contains everything writers need to write with structure and style—all in one convenient app.

Screenshots

Number Builder4 screens
IEW Writing Toolbox4 screens

Verdict

The call

The clearest difference is price: Number Builder at Free against IEW Writing Toolbox's $1.99. IEW Writing Toolbox's advantage is in-app purchases (none vs 1) and update cadence (every 5 weeks vs every 39 months). On 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

Number Builder is free to download; IEW Writing Toolbox costs $1.99 up front. Number Builder sells 1 one-off in-app purchase. IEW Writing Toolbox asks for nothing beyond the download.

UpkeepUpdate frequency

Number Builder ships an update every 39 months, IEW Writing Toolbox every 5 weeks. The most recent releases landed on October 10, 2026 and October 14, 2026 respectively.

Scorecard5 real differences · 6 level
Number Builder versus IEW Writing Toolbox: the parameters behind the verdict, then further details
ParameterNumber BuilderIEW Writing Toolbox
PriceFree — better$1.99
Rating4.9 (7 ratings) — better—
Positive reviews80.0% of reviews—
Number of ratings7 — better—
Update frequencyEvery 39 monthsEvery 5 weeks — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree—
Best chart rank—#60 — better
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS17.013.0 — better
Further details — not scored
Size4 MB53 MB
Age rating4+4+
DeveloperWidgetilities LLCInstitute for Excellence in Writing

In-app purchases

1 purchases

Number Builder

One-time1
  • Unlock Challenge Mode$1.99
None

IEW Writing Toolbox

No in-app purchases

Questions

Is Number Builder free?
Number Builder is free to download, with in-app purchases available.
Is IEW Writing Toolbox free?
IEW Writing Toolbox costs $1.99, with no in-app purchases.
Do Number Builder or IEW Writing Toolbox have ads?
Neither Number Builder nor IEW Writing Toolbox shows ads.
Which is updated more often, Number Builder or IEW Writing Toolbox?
Number Builder ships an update every 39 months, and IEW Writing Toolbox every 5 weeks. Most recently, Number Builder was updated on October 10, 2026 and IEW Writing Toolbox on October 14, 2026.

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