# Serendipity Chess vs Opening Prep

The clearest difference is update cadence: Opening Prep at every 4 days against Serendipity Chess's every 3 weeks. Opening Prep also leads on iOS requirement (16.6 vs 18.0). 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.

Serendipity Chess ships an update every 3 weeks, Opening Prep every 4 days. The most recent releases landed on October 25, 2026 and October 28, 2026 respectively.

## The numbers

| Metric | Serendipity Chess | Opening Prep |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Every 4 days** |
| Size | 67 MB | 5 MB |
| Requires iOS | 18.0 | **16.6** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Mingo Lam](https://appshunter.io/developer/1808874025) | [Roman Bogatenko](https://appshunter.io/developer/1896131806) |

## What reviewers say

### Serendipity Chess

[App page](https://appshunter.io/ios/app/serendipity-chess/id6744680166)

**In-app purchases:** none


### Opening Prep

[App page](https://appshunter.io/ios/app/opening-prep-chess-trainer/id6765937133)

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

**In-app purchases:** none


## Frequently asked questions

### Is Serendipity Chess free?

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

### Is Opening Prep free?

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

### Do Serendipity Chess or Opening Prep have ads?

Neither Serendipity Chess nor Opening Prep shows ads.

### Which is updated more often, Serendipity Chess or Opening Prep?

Serendipity Chess ships an update every 3 weeks, and Opening Prep every 4 days. Most recently, Serendipity Chess was updated on October 25, 2026 and Opening Prep on October 28, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*