# Cardiovascular System QZ vs Study Surfers

The clearest difference is price: Study Surfers at Free against Cardiovascular System QZ's $1.99. Study Surfers also leads on update cadence (every 3 days vs every 24 months). Cardiovascular System QZ's advantage is in-app purchases (none vs 1) and ads (none vs shown). On device support there is nothing between them.

Study Surfers is free to download; Cardiovascular System QZ costs $1.99 up front. Study Surfers sells 1 one-off in-app purchase. Cardiovascular System QZ asks for nothing beyond the download.

Cardiovascular System QZ ships an update every 24 months, Study Surfers every 3 days. The most recent releases landed on October 29, 2026 and November 5, 2026 respectively.

## The numbers

| Metric | Cardiovascular System QZ | Study Surfers |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | — | **[4.6 (9 ratings)](https://appshunter.io/ios/app/study-surfers/id6752008601/reviews)** |
| Number of ratings | — | **9** |
| Positive reviews | — | 50.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 24 months | **Every 3 days** |
| Monetization | — | Free with in-app purchases |
| Size | 56 MB | 241 MB |
| Requires iOS | **12.0** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Alpha Dog Marketing LLC](https://appshunter.io/developer/1532429744) | [Henry Hinman Whittle](https://appshunter.io/developer/1837850814) |

## What reviewers say

### Cardiovascular System QZ

[App page](https://appshunter.io/ios/app/cardiovascular-system-qz/id1584219817)

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

**In-app purchases:** none


### Study Surfers

[App page](https://appshunter.io/ios/app/study-surfers/id6752008601)

This app transforms study notes into an engaging endless runner game. Use AI to generate custom quizzes from any topic, test your knowledge to increase speed, and compete for high scores. Customize your character with earned in-game currency.

**Highlights:** AI-generated custom quizzes, Endless runner gameplay, Speed increases with correct answers, Character customization, High score competition, Unlockable outfits and accessories

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $8.99 | one-time |


## Frequently asked questions

### Is Cardiovascular System QZ free?

Cardiovascular System QZ costs $1.99, with no in-app purchases.

### Is Study Surfers free?

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

### Do Cardiovascular System QZ or Study Surfers have ads?

Study Surfers shows ads; Cardiovascular System QZ does not.

### Which is updated more often, Cardiovascular System QZ or Study Surfers?

Cardiovascular System QZ ships an update every 24 months, and Study Surfers every 3 days. Most recently, Cardiovascular System QZ was updated on October 29, 2026 and Study Surfers on November 5, 2026.

---

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