# Flyback Transformer Designer vs Transformer Calculation Tool

The clearest difference is update cadence: Transformer Calculation Tool at every 4 weeks against Flyback Transformer Designer's every 2 months. Transformer Calculation Tool also leads on iOS requirement (13.0 vs 15.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Flyback Transformer Designer sells 1 in-app purchase, starting at $29.99 per year and Transformer Calculation Tool sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Flyback Transformer Designer ships an update every 2 months, Transformer Calculation Tool every 4 weeks. The most recent releases landed on September 23, 2026 and September 16, 2026 respectively.

## The numbers

| Metric | Flyback Transformer Designer | Transformer Calculation Tool |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 4 weeks** |
| Size | 8 MB | 57 MB |
| Requires iOS | 15.0 | **13.0** |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [建忠 徐](https://appshunter.io/developer/1871049057) | [Shraddhaben Parmar](https://appshunter.io/developer/1889769325) |

## What reviewers say

### Flyback Transformer Designer

[App page](https://appshunter.io/ios/app/flyback-transformer-designer/id6771727431)

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Annual subscription | $29.99 | per year |


### Transformer Calculation Tool

[App page](https://appshunter.io/ios/app/transformer-calculation-tool/id6772152007)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Lifetime premium | $9.99 | one-time |


## Frequently asked questions

### Is Flyback Transformer Designer free?

Flyback Transformer Designer is free to download, with in-app purchases available.

### Is Transformer Calculation Tool free?

Transformer Calculation Tool is free to download, with in-app purchases available.

### Do Flyback Transformer Designer or Transformer Calculation Tool have ads?

Neither Flyback Transformer Designer nor Transformer Calculation Tool shows ads.

### Which is updated more often, Flyback Transformer Designer or Transformer Calculation Tool?

Flyback Transformer Designer ships an update every 2 months, and Transformer Calculation Tool every 4 weeks. Most recently, Flyback Transformer Designer was updated on September 23, 2026 and Transformer Calculation Tool on September 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.*