# K inventory vs PistonR

The clearest difference is update cadence: PistonR at every 3 weeks against K inventory's every 2 months. On price, ads, in-app purchases and device support there is nothing between them.

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

K inventory ships an update every 2 months, PistonR every 3 weeks. The most recent releases landed on October 13, 2026 and October 1, 2026 respectively.

## The numbers

| Metric | K inventory | PistonR |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 3 weeks** |
| Size | 21 MB | 52 MB |
| Requires iOS | 15.0 | **14.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [K-Technology & Services](https://appshunter.io/developer/1596117281) | [Roadoo](https://appshunter.io/developer/1052263761) |

## What reviewers say

### K inventory

[App page](https://appshunter.io/ios/app/k-inventory/id1596902450)

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

**In-app purchases:** none


### PistonR

[App page](https://appshunter.io/ios/app/pistonr/id1620543201)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is K inventory free?

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

### Is PistonR free?

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

### Do K inventory or PistonR have ads?

Neither K inventory nor PistonR shows ads.

### Which is updated more often, K inventory or PistonR?

K inventory ships an update every 2 months, and PistonR every 3 weeks. Most recently, K inventory was updated on October 13, 2026 and PistonR on October 1, 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.*