# 피아노 레슨 카드 vs String AI

The clearest difference is in-app purchases: 피아노 레슨 카드 at none against String AI's 4. 피아노 레슨 카드 also leads on update cadence (daily vs every 2 weeks) and iOS requirement (13.0 vs 15.1). On price, ads and device support there is nothing between them.

Both are free to download. String AI sells 4 in-app purchases, starting at $14.99 per month. 피아노 레슨 카드 asks for nothing beyond the download.

피아노 레슨 카드 ships an update daily, String AI every 2 weeks. The most recent releases landed on September 29, 2026 and September 27, 2026 respectively.

## The numbers

| Metric | 피아노 레슨 카드 | String AI |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.2 (5 ratings)](https://appshunter.io/ios/app/string-ai-strings-practice/id6787829281/reviews)** |
| Number of ratings | — | **5** |
| Positive reviews | — | 80.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Daily** | Every 2 weeks |
| Monetization | — | Free with in-app purchases |
| Size | 21 MB | 95 MB |
| Requires iOS | **13.0** | 15.1 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Shinhye Lee](https://appshunter.io/developer/1707333313) | [Youna Choi](https://appshunter.io/developer/6787829283) |

## What reviewers say

### 피아노 레슨 카드

[App page](https://appshunter.io/ios/app/id6760224601)

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

**In-app purchases:** none


### String AI

[App page](https://appshunter.io/ios/app/string-ai-strings-practice/id6787829281)

This AI-powered coach provides real-time feedback on your violin, viola, or cello practice, analyzing intonation, rhythm, tone, dynamics, and posture. It structures your sessions like a lesson, diagnoses issues, and prescribes targeted drills to improve your playing habits.

**Highlights:** Real-time note and form analysis, Five-axis scoring (intonation, rhythm, tone, dynamics, posture), Instrument-specific feedback for violin, viola, cello, Personalized practice session planning, Targeted drills for weak spots, Optional teacher integration for progress sharing

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

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Basic | $14.99 | per month |
| Casual | $29.99 | per month |
| Standard | $44.99 | per month |
| Pro | $59.99 | per month |


## Frequently asked questions

### Is 피아노 레슨 카드 free?

피아노 레슨 카드 is free to download, with no in-app purchases.

### Is String AI free?

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

### Do 피아노 레슨 카드 or String AI have ads?

Neither 피아노 레슨 카드 nor String AI shows ads.

### Which is updated more often, 피아노 레슨 카드 or String AI?

피아노 레슨 카드 ships an update daily, and String AI every 2 weeks. Most recently, 피아노 레슨 카드 was updated on September 29, 2026 and String AI on September 27, 2026.

---

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