# Timer 555 Calculator Pro vs PCB Studio Maker

The clearest difference is price: PCB Studio Maker at Free against Timer 555 Calculator Pro's $0.99. PCB Studio Maker also leads on update cadence (every 3 days vs every 3 months). Timer 555 Calculator Pro's advantage is in-app purchases (none vs 1) and iOS requirement (13.2 vs 17.6). On ads and device support there is nothing between them.

PCB Studio Maker is free to download; Timer 555 Calculator Pro costs $0.99 up front. PCB Studio Maker sells 1 in-app purchase, starting at $4.99 per month. Timer 555 Calculator Pro asks for nothing beyond the download.

Timer 555 Calculator Pro ships an update every 3 months, PCB Studio Maker every 3 days. The most recent releases landed on October 10, 2026 and October 16, 2026 respectively.

## The numbers

| Metric | Timer 555 Calculator Pro | PCB Studio Maker |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | **[4.7 (3 ratings)](https://appshunter.io/ios/app/timer-555-calculator-pro/id833443125/reviews)** | — |
| Number of ratings | **3** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 3 days** |
| Monetization | Paid | — |
| Size | 3 MB | 11 MB |
| Requires iOS | **13.2** | 17.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, Mac |
| Age rating | 4+ | 4+ |
| Developer | [Siu Yuen Ho](https://appshunter.io/developer/814088527) | [Mirza Pasic](https://appshunter.io/developer/1863048976) |

## What reviewers say

### Timer 555 Calculator Pro

[App page](https://appshunter.io/ios/app/timer-555-calculator-pro/id833443125)

Calculate parameters for monostable and astable circuits. Find component combinations for desired pulse width or frequency. Share circuit files via iCloud Drive or AirDrop.

**Highlights:** Calculate monostable pulse width, Calculate astable frequency, Find component combinations, Adjust component tolerance, Unlimited combinations (Pro), Share circuit files

**In-app purchases:** none


### PCB Studio Maker

[App page](https://appshunter.io/ios/app/pcb-studio-maker/id6812477674)

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| PCB Studio Pro | $4.99 | per month |


## Frequently asked questions

### Is Timer 555 Calculator Pro free?

Timer 555 Calculator Pro costs $0.99, with no in-app purchases.

### Is PCB Studio Maker free?

PCB Studio Maker is free to download, with in-app purchases available.

### Do Timer 555 Calculator Pro or PCB Studio Maker have ads?

Neither Timer 555 Calculator Pro nor PCB Studio Maker shows ads.

### Which is updated more often, Timer 555 Calculator Pro or PCB Studio Maker?

Timer 555 Calculator Pro ships an update every 3 months, and PCB Studio Maker every 3 days. Most recently, Timer 555 Calculator Pro was updated on October 10, 2026 and PCB Studio Maker on October 16, 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.*