# Cluster2A vs Combine PDF Files

The clearest difference is price: Cluster2A at Free against Combine PDF Files's $0.99. Combine PDF Files's advantage is in-app purchases (none vs 2) and update cadence (fortnightly vs every 3 months). On ads there is nothing between them.

Cluster2A is free to download; Combine PDF Files costs $0.99 up front. Cluster2A sells 2 one-off in-app purchases. Combine PDF Files asks for nothing beyond the download.

Cluster2A ships an update every 3 months, Combine PDF Files fortnightly. The most recent releases landed on October 4, 2026 and October 12, 2026 respectively.

## The numbers

| Metric | Cluster2A | Combine PDF Files |
| --- | --- | --- |
| Price | **Free** | $0.99 |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 3 months | **Fortnightly** |
| Size | 9 MB | 2 MB |
| Requires iOS | 26.2 | **15.6** |
| Devices | iPhone | **iPhone, iPad, iPod, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [Chu-Yi Chang](https://appshunter.io/developer/943416679) | [Mike West](https://appshunter.io/developer/1815075434) |

## What reviewers say

### Cluster2A

[App page](https://appshunter.io/ios/app/cluster2a/id1544599436)

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| K-means Model | $1.99 | one-time |
| DBSCAN Model | $1.99 | one-time |


### Combine PDF Files

[App page](https://appshunter.io/ios/app/combine-pdf-files/id6755452166)

**In-app purchases:** none


## Frequently asked questions

### Is Cluster2A free?

Cluster2A is free to download, with in-app purchases available.

### Is Combine PDF Files free?

Combine PDF Files costs $0.99, with no in-app purchases.

### Do Cluster2A or Combine PDF Files have ads?

Neither Cluster2A nor Combine PDF Files shows ads.

### Which is updated more often, Cluster2A or Combine PDF Files?

Cluster2A ships an update every 3 months, and Combine PDF Files fortnightly. Most recently, Cluster2A was updated on October 4, 2026 and Combine PDF Files on October 12, 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.*