# API 510 Highlights Practices vs API Inspector Cert Prep

The clearest difference is in-app purchases: API 510 Highlights Practices at none against API Inspector Cert Prep's 3. API 510 Highlights Practices also leads on iOS requirement (9.1 vs 15.1). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. API Inspector Cert Prep sells 3 one-off in-app purchases. API 510 Highlights Practices asks for nothing beyond the download.

API 510 Highlights Practices ships an update every 2 months, API Inspector Cert Prep every 3 months. The most recent releases landed on October 1, 2026 and October 2, 2026 respectively.

## The numbers

| Metric | API 510 Highlights Practices | API Inspector Cert Prep |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 2 months** | Every 3 months |
| Size | 16 MB | 32 MB |
| Requires iOS | **9.1** | 15.1 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Nguyen Hieu](https://appshunter.io/developer/1323491316) | [Simon Shih](https://appshunter.io/developer/1870707682) |

## What reviewers say

### API 510 Highlights Practices

[App page](https://appshunter.io/ios/app/api-510-highlights-practices/id1362433334)

**Features:** macOS Compatibility

**In-app purchases:** none


### API Inspector Cert Prep

[App page](https://appshunter.io/ios/app/api-inspector-cert-prep/id6785875538)

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| API 510 – Pressure Vessel Inspector | $19.99 | one-time |
| API 570 – Piping Inspector | $19.99 | one-time |
| API 653 – Storage Tank Inspector | $19.99 | one-time |


## Frequently asked questions

### Is API 510 Highlights Practices free?

API 510 Highlights Practices is free to download, with no in-app purchases.

### Is API Inspector Cert Prep free?

API Inspector Cert Prep is free to download, with in-app purchases available.

### Do API 510 Highlights Practices or API Inspector Cert Prep have ads?

Neither API 510 Highlights Practices nor API Inspector Cert Prep shows ads.

### Which is updated more often, API 510 Highlights Practices or API Inspector Cert Prep?

API 510 Highlights Practices ships an update every 2 months, and API Inspector Cert Prep every 3 months. Most recently, API 510 Highlights Practices was updated on October 1, 2026 and API Inspector Cert Prep on October 2, 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.*