# Piano ∞ vs IDOUDO

The clearest difference is update cadence: IDOUDO at every 3 weeks against Piano ∞'s every 9 months. Piano ∞'s advantage is iOS requirement (13.0 vs 17.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Piano ∞ sells 4 in-app purchases, starting at $2.99 per 7 days and IDOUDO sells 12 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

Piano ∞ ships an update every 9 months, IDOUDO every 3 weeks. The most recent releases landed on October 21, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Piano ∞ | IDOUDO |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.4 (567 ratings)](https://appshunter.io/ios/app/piano/id485362757/reviews)** | — |
| Number of ratings | **567** | — |
| Positive reviews | 79.1% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 9 months | **Every 3 weeks** |
| Monetization | Free with in-app purchases | — |
| Size | 88 MB | 3 MB |
| Requires iOS | **13.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Better Day Wireless, Inc.](https://appshunter.io/developer/287963852) | [Kosuke Mawatari](https://appshunter.io/developer/1489564137) |

## What reviewers say

### Piano ∞

[App page](https://appshunter.io/ios/app/piano/id485362757)

This app offers a comprehensive piano experience with five instruments, sheet music, lessons, and composing tools. It features AI-powered sheet music progression and realistic sound. An optional subscription unlocks a vast song catalog and advanced creation features.

**Highlights:** Five instrument options, Interactive sheet music, AI-powered lesson progression, Composing and recording tools, Realistic concert grand piano sound, Play-along feature

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

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlimited Use | $2.99 | per 7 days |
| Unlimited Use | $9.99 | per 3 months |
| 1 Month Music Studio Pass | $9.99 | per month |
| Unlimited Use | $59.99 | per year |

**What reviewers like**

- 🎹 Realistic piano sound
- 🎓 Helpful for learning piano
- 👍 Easy to use and navigate
- 🎶 Fun and entertaining

**What reviewers complain about**

- 💰 Limited free content, requires subscription
- 🐛 Occasional crashes or bugs
- 📏 Keyboard size too small for some users
- 🔇 Difficulty hearing melody in some songs

**Reported bugs**

- Subscription auto-renewal issues
- Keyboard not responsive at times
- Certain notes or pitches sound off-key

**Requested features**

- Add more free songs and content
- Allow users to import their own songs
- Improve note visualization and scrolling
- Add more advanced music editing tools


### IDOUDO

[App page](https://appshunter.io/ios/app/idoudo-movable-do-solfege/id6804583806)

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

**In-app purchases (12)**

| Purchase | Price | Billing |
| --- | --- | --- |
| All Drills (Monthly) | $2.99 | per month |
| All Drills (Yearly) | $19.99 | per year |
| Unlock All Keys: Ear 2 Notes | $1.99 | one-time |
| Unlock All Keys: Ear 3 Notes | $1.99 | one-time |
| Unlock All Keys: Ear 4 Notes | $1.99 | one-time |
| Unlock All Keys: Major Set 1 | $1.99 | one-time |
| Unlock All Keys: Minor Set 1 | $1.99 | one-time |
| Unlock All Keys: Major Set 2 | $1.99 | one-time |
| Unlock All Keys: 1 Note | $1.99 | one-time |
| Unlock All Keys: 2 Notes | $1.99 | one-time |
| Unlock All Keys: 1 Triad | $1.99 | one-time |
| Unlock Keys: 1 Seventh Chord | $1.99 | one-time |


## Frequently asked questions

### Is Piano ∞ free?

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

### Is IDOUDO free?

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

### Do Piano ∞ or IDOUDO have ads?

Neither Piano ∞ nor IDOUDO shows ads.

### Which is updated more often, Piano ∞ or IDOUDO?

Piano ∞ ships an update every 9 months, and IDOUDO every 3 weeks. Most recently, Piano ∞ was updated on October 21, 2026 and IDOUDO on October 24, 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.*