# Simple Circuit Builder vs Black Reader

The clearest difference is in-app purchases: Simple Circuit Builder at none against Black Reader's 1. Black Reader's advantage is update cadence (every 3 days vs every 3 weeks). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Black Reader sells 1 one-off in-app purchase. Simple Circuit Builder asks for nothing beyond the download.

Simple Circuit Builder ships an update every 3 weeks, Black Reader every 3 days. The most recent releases landed on November 3, 2026 and October 8, 2026 respectively.

## The numbers

| Metric | Simple Circuit Builder | Black Reader |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.0 (28 ratings)](https://appshunter.io/ios/app/simple-circuit-builder/id1294616098/reviews)** | — |
| Number of ratings | **28** | — |
| Positive reviews | 52.6% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Every 3 days** |
| Monetization | Free | — |
| Size | 14 MB | 31 MB |
| Requires iOS | **14.0** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [David White](https://appshunter.io/developer/911163945) | [ZAKARIA ELAROUSSI](https://appshunter.io/developer/1895555101) |

## What reviewers say

### Simple Circuit Builder

[App page](https://appshunter.io/ios/app/simple-circuit-builder/id1294616098)

This virtual lab offers a hands-on experience for learning about resistors and circuit resistance. Easily build and test series and parallel circuits, measure voltage and current, and understand the impact of component changes in real-time.

**Highlights:** Build circuits with up to eight components, Five component types, Virtual volt and amp meters, Adjustable resistor and voltage values, Real-time circuit analysis, Demonstrates 'Opens' and 'Shorts'

**Features:** macOS Compatibility

**In-app purchases:** none


### Black Reader

[App page](https://appshunter.io/ios/app/black-reader-pdf-reader/id6800425465)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Black Reader PRO | $0.99 | one-time |


## Frequently asked questions

### Is Simple Circuit Builder free?

Simple Circuit Builder is free to download, with no in-app purchases.

### Is Black Reader free?

Black Reader is free to download, with in-app purchases available.

### Do Simple Circuit Builder or Black Reader have ads?

Neither Simple Circuit Builder nor Black Reader shows ads.

### Which is updated more often, Simple Circuit Builder or Black Reader?

Simple Circuit Builder ships an update every 3 weeks, and Black Reader every 3 days. Most recently, Simple Circuit Builder was updated on November 3, 2026 and Black Reader on October 8, 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.*