# Invisible Ping Pong vs KnowDown

The clearest difference is rating: KnowDown at 5.0 against Invisible Ping Pong's 3.7. KnowDown also leads on iOS requirement (15.1 vs 17.0). Invisible Ping Pong's advantage is update cadence (every 2 days vs weekly) and ratings volume (3 vs 1). On price, ads, in-app purchases and monetization model there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

KnowDown holds the better App Store score, 5.0 against 3.7. Both are backed by a comparable volume of ratings — 3 and 1 respectively.

Invisible Ping Pong ships an update every 2 days, KnowDown weekly. The most recent releases landed on October 24, 2026 and October 21, 2026 respectively.

## The numbers

| Metric | Invisible Ping Pong | KnowDown |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.7 (3 ratings)](https://appshunter.io/ios/app/invisible-ping-pong/id6502412114/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/knowdown/id6761421487/reviews)** |
| Number of ratings | **3** | 1 |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 2 days** | Weekly |
| Monetization | Free | Free |
| Size | 14 MB | 35 MB |
| Requires iOS | 17.0 | **15.1** |
| Devices | iPhone | **iPhone, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Matteo Perotta](https://appshunter.io/developer/1822731774) | [Niklas Debbrecht](https://appshunter.io/developer/1889520130) |

## What reviewers say

### Invisible Ping Pong

[App page](https://appshunter.io/ios/app/invisible-ping-pong/id6502412114)

Experience table tennis without physical equipment. Use your phone as a racket and mimic swing gestures to play against friends or a bot. Enjoy a unique 1v1 multiplayer experience anywhere.

**Highlights:** Play table tennis virtually, Use phone as racket, Gesture-based swing detection, 1v1 multiplayer against friends, Train against AI bot, No physical equipment needed

**Features:** macOS Compatibility

**In-app purchases:** none


### KnowDown

[App page](https://appshunter.io/ios/app/knowdown/id6761421487)

A trivia game that measures your knowledge with an ELO rating system. Answer questions across various categories, compete on global leaderboards, and learn from your mistakes. Offers daily limits and streak bonuses.

**Highlights:** ELO rating system for skill measurement, 700+ curated trivia questions, Global leaderboards, Smart matchmaking based on ELO, Daily question limit, Day streaks and awards, Answer history for learning

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

**In-app purchases:** none


## Frequently asked questions

### Is Invisible Ping Pong free?

Invisible Ping Pong is free to download, with no in-app purchases.

### Is KnowDown free?

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

### Which has better reviews, Invisible Ping Pong or KnowDown?

KnowDown is rated higher. Invisible Ping Pong averages 3.7 out of 5 from 3 ratings, while KnowDown averages 5.0 from 1 ratings.

### Do Invisible Ping Pong or KnowDown have ads?

Neither Invisible Ping Pong nor KnowDown shows ads.

### Which is updated more often, Invisible Ping Pong or KnowDown?

Invisible Ping Pong ships an update every 2 days, and KnowDown weekly. Most recently, Invisible Ping Pong was updated on October 24, 2026 and KnowDown on October 21, 2026.

---

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