# Sieslack vs Kleos

The clearest difference is ads: Sieslack at none against Kleos's shown. On price, update cadence, 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.

Sieslack ships an update every 8 months, Kleos every 5 months. The most recent releases landed on October 5, 2026 and October 11, 2026 respectively.

## The numbers

| Metric | Sieslack | Kleos |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 8 months | **Every 5 months** |
| Size | 58 MB | 393 MB |
| Requires iOS | **11.0** | 12.4 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Wolters Kluwer Tax & Accounting Deutschland GmbH](https://appshunter.io/developer/439837413) | [Wolters Kluwer](https://appshunter.io/developer/395677482) |

## What reviewers say

### Sieslack

[App page](https://appshunter.io/ios/app/sieslack-app/id929034602)

**In-app purchases:** none


### Kleos

[App page](https://appshunter.io/ios/app/kleos/id1632200975)

**In-app purchases:** none


## Frequently asked questions

### Is Sieslack free?

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

### Is Kleos free?

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

### Do Sieslack or Kleos have ads?

Kleos shows ads; Sieslack does not.

### Which is updated more often, Sieslack or Kleos?

Sieslack ships an update every 8 months, and Kleos every 5 months. Most recently, Sieslack was updated on October 5, 2026 and Kleos on October 11, 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.*