# istas21 vs P4Work

The clearest difference is update cadence: P4Work at every 3 months against istas21's every 15 months. istas21's advantage is iOS requirement (7.0 vs 13.0). 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.

istas21 ships an update every 15 months, P4Work every 3 months. The most recent releases landed on October 26, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | istas21 | P4Work |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 15 months | **Every 3 months** |
| Size | 25 MB | 20 MB |
| Requires iOS | **7.0** | 13.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [SPL SISTEMAS DE INFORMACION, SL](https://appshunter.io/developer/482938841) | [GeoSLab](https://appshunter.io/developer/830485894) |

## What reviewers say

### istas21

[App page](https://appshunter.io/ios/app/istas21/id1118374567)

**Features:** macOS Compatibility

**In-app purchases:** none


### P4Work

[App page](https://appshunter.io/ios/app/p4work/id1509417286)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is istas21 free?

istas21 is free to download, with no in-app purchases.

### Is P4Work free?

P4Work is free to download, with no in-app purchases.

### Do istas21 or P4Work have ads?

Neither istas21 nor P4Work shows ads.

### Which is updated more often, istas21 or P4Work?

istas21 ships an update every 15 months, and P4Work every 3 months. Most recently, istas21 was updated on October 26, 2026 and P4Work 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.*