# LineKeeper vs PLC Ninja

The clearest difference is update cadence: LineKeeper at every 4 days against PLC Ninja's every 3 weeks. LineKeeper also leads on device support (3 vs 1) and iOS requirement (15.0 vs 17.6). On price, ads and in-app purchases there is nothing between them.

Both are free to download. LineKeeper sells 1 one-off in-app purchase and PLC Ninja sells 6 in-app purchases, starting at $3.99 per month. Whichever you choose, the download price is not the number that matters.

LineKeeper ships an update every 4 days, PLC Ninja every 3 weeks. The most recent releases landed on October 4, 2026 and October 5, 2026 respectively.

## The numbers

| Metric | LineKeeper | PLC Ninja |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (3 ratings)](https://appshunter.io/ios/app/plc-ninja/id6805188950/reviews)** |
| Number of ratings | — | **3** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Every 4 days** | Every 3 weeks |
| Monetization | — | Free with in-app purchases |
| Size | 19 MB | 10 MB |
| Requires iOS | **15.0** | 17.6 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Oleksandr Makarov](https://appshunter.io/developer/6791371576) | [SHAOHUA YI](https://appshunter.io/developer/6805189132) |

## What reviewers say

### LineKeeper

[App page](https://appshunter.io/ios/app/linekeeper/id6791371574)

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Write Unlock | $59.99 | one-time |


### PLC Ninja

[App page](https://appshunter.io/ios/app/plc-ninja/id6805188950)

Access live PLC data directly from your mobile device. Connect via Ethernet, Wi-Fi, or serial adapter to monitor inputs, outputs, timers, counters, and analog values in real-time while in the field.

**Highlights:** Real-time PLC data monitoring, Ethernet, Wi-Fi, and serial connection support, View inputs and outputs, Monitor timers and counters, Access analog values

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

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Standard | $3.99 | per month |
| Professional | $8.99 | per month |
| Ultimate | $14.99 | per month |
| Standard | $39.99 | per year |
| Professional | $89.99 | per year |
| Ultimate | $149.99 | per year |


## Frequently asked questions

### Is LineKeeper free?

LineKeeper is free to download, with in-app purchases available.

### Is PLC Ninja free?

PLC Ninja is free to download, with in-app purchases available.

### Do LineKeeper or PLC Ninja have ads?

Neither LineKeeper nor PLC Ninja shows ads.

### Which is updated more often, LineKeeper or PLC Ninja?

LineKeeper ships an update every 4 days, and PLC Ninja every 3 weeks. Most recently, LineKeeper was updated on October 4, 2026 and PLC Ninja on October 5, 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.*