# Happy Kitty Calculator vs ZeroNAS

The clearest difference is in-app purchases: ZeroNAS at none against Happy Kitty Calculator's 1. On price, update cadence, ads and device support there is nothing between them.

Both are free to download. Happy Kitty Calculator sells 1 one-off in-app purchase. ZeroNAS asks for nothing beyond the download.

Happy Kitty Calculator ships an update every 3 weeks, ZeroNAS every 2 weeks. Both last shipped on October 25, 2026.

## The numbers

| Metric | Happy Kitty Calculator | ZeroNAS |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[1.0 (5 ratings)](https://appshunter.io/ios/app/zeronas/id6754591921/reviews)** |
| Number of ratings | — | **5** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Every 2 weeks** |
| Monetization | — | Free |
| Size | 59 MB | 143 MB |
| Requires iOS | 15.6 | **15.0** |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [HUA-TENG HUANG](https://appshunter.io/developer/1780056727) | [Fujian Centerm Information Co., Ltd](https://appshunter.io/developer/807316807) |

## What reviewers say

### Happy Kitty Calculator

[App page](https://appshunter.io/ios/app/happy-kitty-calculator/id6739179959)

**Features:** Family Sharing, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| One-time purchase. | $2.99 | one-time |


### ZeroNAS

[App page](https://appshunter.io/ios/app/zeronas/id6754591921)

This app acts as a smart personal data hub, offering a private theater experience, secure remote work capabilities, and stable smart home integration. It features AI-powered photo organization and robust data security with multi-mode RAID support and data isolation.

**Highlights:** Private theater with auto poster matching, AI photo management with face recognition, Secure remote access to files, Multi-mode RAID support for data protection, Data isolation and multi-user permissions, Pure local mode for cloud-free operation, Built-in Docker engine for app deployment

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

**In-app purchases:** none


## Frequently asked questions

### Is Happy Kitty Calculator free?

Happy Kitty Calculator is free to download, with in-app purchases available.

### Is ZeroNAS free?

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

### Do Happy Kitty Calculator or ZeroNAS have ads?

Neither Happy Kitty Calculator nor ZeroNAS shows ads.

### Which is updated more often, Happy Kitty Calculator or ZeroNAS?

Happy Kitty Calculator ships an update every 3 weeks, and ZeroNAS every 2 weeks. Most recently, Happy Kitty Calculator was updated on October 25, 2026 and ZeroNAS 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.*