# IDOUDO vs Piano Note Reading Drill

The clearest difference is update cadence: Piano Note Reading Drill at every 3 days against IDOUDO's every 3 weeks. IDOUDO's advantage is iOS requirement (17.0 vs 26.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. IDOUDO sells 12 in-app purchases, starting at $2.99 per month and Piano Note Reading Drill sells 3 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

IDOUDO ships an update every 3 weeks, Piano Note Reading Drill every 3 days. Both last shipped on October 24, 2026.

## The numbers

| Metric | IDOUDO | Piano Note Reading Drill |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Every 3 days** |
| Size | 3 MB | 18 MB |
| Requires iOS | **17.0** | 26.0 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Kosuke Mawatari](https://appshunter.io/developer/1489564137) | [Ruku Kobayashi](https://appshunter.io/developer/1707735136) |

## What reviewers say

### 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 |


### Piano Note Reading Drill

[App page](https://appshunter.io/ios/app/piano-note-reading-drill/id6809145060)

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Snack Tip | $0.49 | one-time |
| Coffee Tip | $2.99 | one-time |
| Dinner Tip | $5.99 | one-time |


## Frequently asked questions

### Is IDOUDO free?

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

### Is Piano Note Reading Drill free?

Piano Note Reading Drill is free to download, with in-app purchases available.

### Do IDOUDO or Piano Note Reading Drill have ads?

Neither IDOUDO nor Piano Note Reading Drill shows ads.

### Which is updated more often, IDOUDO or Piano Note Reading Drill?

IDOUDO ships an update every 3 weeks, and Piano Note Reading Drill every 3 days. Most recently, IDOUDO was updated on October 24, 2026 and Piano Note Reading Drill 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.*