# Number Builder vs IEW Writing Toolbox

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.

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.

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.

## The numbers

| Metric | Number Builder | IEW Writing Toolbox |
| --- | --- | --- |
| Price | **Free** | $1.99 |
| Rating | **[4.9 (7 ratings)](https://appshunter.io/ios/app/number-builder-puzzle-solver/id1489526164/reviews)** | — |
| Number of ratings | **7** | — |
| Positive reviews | 80.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 39 months | **Every 5 weeks** |
| Monetization | Free | — |
| Best chart rank | — | **#71** |
| Size | 4 MB | 53 MB |
| Requires iOS | 17.0 | **13.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Widgetilities LLC](https://appshunter.io/developer/1373578566) | [Institute for Excellence in Writing](https://appshunter.io/developer/587466824) |

## What reviewers say

### Number Builder

[App page](https://appshunter.io/ios/app/number-builder-puzzle-solver/id1489526164)

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:** macOS Compatibility, Family Sharing, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlock Challenge Mode | $1.99 | one-time |


### IEW Writing Toolbox

[App page](https://appshunter.io/ios/app/iew-writing-toolbox/id6753764743)

**Currently charting:** #71 Top Paid · Education (US App Store)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked 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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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*