# NPD知识普及 vs NPD对抗21天

The clearest difference is price: NPD对抗21天 at Free against NPD知识普及's $0.99. NPD知识普及's advantage is in-app purchases (none vs 1). On ads, device support and iOS requirement there is nothing between them.

NPD对抗21天 is free to download; NPD知识普及 costs $0.99 up front. NPD对抗21天 sells 1 one-off in-app purchase. NPD知识普及 asks for nothing beyond the download.

## The numbers

| Metric | NPD知识普及 | NPD对抗21天 |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 7 months | — |
| Monetization | Paid | — |
| Size | 3 MB | 4 MB |
| Requires iOS | 18.5 | **17.6** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Guangdong Jianchuan Information Technology Co., Ltd](https://appshunter.io/developer/1822428404) | [阳 孙](https://appshunter.io/developer/1518808403) |

## What reviewers say

### NPD知识普及

[App page](https://appshunter.io/ios/app/npd/id6749845582)

This app provides comprehensive knowledge, assessment, coping strategies, and support for individuals interested in Narcissistic Personality Disorder (NPD). It draws from psychological research and clinical experience to help users understand NPD and find professional assistance.

**Highlights:** NPD knowledge base, Self-assessment tools, Coping strategy guidance, Professional support resources, Based on psychological research, Clinical practice experience

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

**In-app purchases:** none


### NPD对抗21天

[App page](https://appshunter.io/ios/app/npd21/id6757114144)

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| NPD对抗21天 Pro | $0.99 | one-time |


## Frequently asked questions

### Is NPD知识普及 free?

NPD知识普及 costs $0.99, with no in-app purchases.

### Is NPD对抗21天 free?

NPD对抗21天 is free to download, with in-app purchases available.

### Do NPD知识普及 or NPD对抗21天 have ads?

Neither NPD知识普及 nor NPD对抗21天 shows ads.

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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.*