# 12tennis vs slamstr

The clearest difference is ads: 12tennis at none against slamstr's shown. 12tennis also leads on iOS requirement (11.0 vs 15.1). 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.

12tennis ships an update monthly, slamstr fortnightly. The most recent releases landed on October 7, 2026 and October 11, 2026 respectively.

## The numbers

| Metric | 12tennis | slamstr |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Monthly | **Fortnightly** |
| Monetization | Free | — |
| Size | 18 MB | 54 MB |
| Requires iOS | **11.0** | 15.1 |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Konrad Swietek](https://appshunter.io/developer/1121654014) | [slamstr GmbH](https://appshunter.io/developer/1746273779) |

## What reviewers say

### 12tennis

[App page](https://appshunter.io/ios/app/12tennis/id1508159372)

Easily book tennis courts online through this app. Reserve your spot at local clubs directly from your smartphone and always stay updated on court availability.

**Highlights:** Online court reservation, Local club booking, Real-time availability tracking, Smartphone booking

**Features:** macOS Compatibility

**In-app purchases:** none


### slamstr

[App page](https://appshunter.io/ios/app/slamstr/id6502635375)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is 12tennis free?

12tennis is free to download, with no in-app purchases.

### Is slamstr free?

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

### Do 12tennis or slamstr have ads?

slamstr shows ads; 12tennis does not.

### Which is updated more often, 12tennis or slamstr?

12tennis ships an update monthly, and slamstr fortnightly. Most recently, 12tennis was updated on October 7, 2026 and slamstr 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.*