# NDT Worldwide vs API 653 helpmate

The clearest difference is update cadence: API 653 helpmate at every 3 weeks against NDT Worldwide's every 16 months. On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. NDT Worldwide sells 10 one-off in-app purchases and API 653 helpmate sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

NDT Worldwide ships an update every 16 months, API 653 helpmate every 3 weeks. The most recent releases landed on October 7, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | NDT Worldwide | API 653 helpmate |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 16 months | **Every 3 weeks** |
| Size | 265 MB | 33 MB |
| Requires iOS | **15.6** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 17+ | 4+ |
| Developer | [WWNDT SERVICES PRIVATE LIMITED](https://appshunter.io/developer/1570208273) | [Austenite Pty Ltd](https://appshunter.io/developer/1525502686) |

## What reviewers say

### NDT Worldwide

[App page](https://appshunter.io/ios/app/ndt-worldwide/id1607234047)

**Features:** macOS Compatibility, Apple Wallet

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| ASTM E165 | $44.99 | one-time |
| ASTM E2582 | $44.99 | one-time |
| ASTM E2375 | $54.99 | one-time |
| ASTM E709 | $54.99 | one-time |
| ASTM E2375 | $69.99 | one-time |
| ASNT MT Level III Examination | $219.99 | one-time |
| ASNT NDT Level III-BASIC | $299.99 | one-time |
| ASNT UT Level III Examination | $299.99 | one-time |
| ASNT ML Level III Examination | $399.99 | one-time |
| ASNT NDT Level III BASIC | $449.99 | one-time |


### API 653 helpmate

[App page](https://appshunter.io/ios/app/api-653-helpmate/id6745550821)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| API 653 Premium - 1 Year Access | $49.99 | one-time |


## Frequently asked questions

### Is NDT Worldwide free?

NDT Worldwide is free to download, with in-app purchases available.

### Is API 653 helpmate free?

API 653 helpmate is free to download, with in-app purchases available.

### Do NDT Worldwide or API 653 helpmate have ads?

Neither NDT Worldwide nor API 653 helpmate shows ads.

### Which is updated more often, NDT Worldwide or API 653 helpmate?

NDT Worldwide ships an update every 16 months, and API 653 helpmate every 3 weeks. Most recently, NDT Worldwide was updated on October 7, 2026 and API 653 helpmate on October 25, 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.*