# Audiologist vs NDST500A

The clearest difference is iOS requirement: NDST500A at 9.0 against Audiologist's 14.0. On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Audiologist ships an update every 3 months, NDST500A every 6 months. Both last shipped on October 10, 2026.

## The numbers

| Metric | Audiologist | NDST500A |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 3 months** | Every 6 months |
| Size | 10 MB | 39 MB |
| Requires iOS | 14.0 | **9.0** |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [欧仕达听力科技(厦门)有限公司](https://appshunter.io/developer/1405345564) | [Guangzhou Aidan Blessindo Electronic Co.,Ltd.](https://appshunter.io/developer/1413008258) |

## What reviewers say

### Audiologist

[App page](https://appshunter.io/ios/app/audiologist/id1405345565)

**In-app purchases:** none


### NDST500A

[App page](https://appshunter.io/ios/app/ndst500a/id1545279044)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Audiologist free?

Audiologist is free to download, with no in-app purchases.

### Is NDST500A free?

NDST500A is free to download, with no in-app purchases.

### Do Audiologist or NDST500A have ads?

Neither Audiologist nor NDST500A shows ads.

### Which is updated more often, Audiologist or NDST500A?

Audiologist ships an update every 3 months, and NDST500A every 6 months. Most recently, Audiologist was updated on October 10, 2026 and NDST500A on October 10, 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.*