# BK vs KORG iM1

The clearest difference is review sentiment: KORG iM1 at 82% against BK's 33%. KORG iM1 also leads on rating (4.7 vs 3.7) and ratings volume (1K vs 3). BK's advantage is price (Free vs $29.99) and in-app purchases (none vs 2). On update cadence and ads there is nothing between them.

BK is free to download; KORG iM1 costs $29.99 up front. KORG iM1 sells 2 one-off in-app purchases. BK asks for nothing beyond the download.

KORG iM1 holds the better App Store score, 4.7 against 3.7. That said, the two scores are not equally well evidenced: KORG iM1 has 1K ratings behind it against 3, so its average is the more settled of the two. Written reviews point the same way: 33% of BK's written reviews are positive against 82% of KORG iM1's.

BK ships an update every 9 months, KORG iM1 every 7 months. The most recent releases landed on October 8, 2026 and October 17, 2026 respectively.

## The numbers

| Metric | BK | KORG iM1 |
| --- | --- | --- |
| Price | **Free** | $29.99 |
| Rating | [3.7 (3 ratings)](https://appshunter.io/ios/app/bk-9-performance-editor/id668979731/reviews) | **[4.7 (1K ratings)](https://appshunter.io/ios/app/korg-im1/id966030326/reviews)** |
| Number of ratings | 3 | **1K** |
| Positive reviews | 33.3% of reviews | **81.5% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 9 months | **Every 7 months** |
| Monetization | **Free** | Free with in-app purchases |
| Best chart rank | — | **#76** |
| Size | 22 MB | 200 MB |
| Requires iOS | **8.1** | 12.0 |
| Devices | iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Roland Corporation](https://appshunter.io/developer/387333694) | [KORG INC.](https://appshunter.io/developer/363714046) |

## What reviewers say

### BK

[App page](https://appshunter.io/ios/app/bk-9-performance-editor/id668979731)

Control and edit the real-time performance parameters of your Roland BK-9 Backing Keyboard directly from your iPad. Enhance your playing, practicing, and composing experience with quick access to tone editing, part mixing, and effects.

**Highlights:** Real-time parameter editing, Tone editing, Part mixing control, Effects adjustment, iPad touchscreen interface, Enhanced performance tool

**In-app purchases:** none


### KORG iM1

[App page](https://appshunter.io/ios/app/korg-im1/id966030326)

**Currently charting:** #76 Top Paid · Music (US App Store)

This app faithfully reproduces the legendary M1 synthesizer, offering its iconic sounds and expanded features for modern music creation. It provides a vast library of presets and intuitive performance tools, making it accessible to both experienced musicians and beginners.

**Highlights:** Faithful reproduction of original M1 sound, Expanded filter resonance and 18 effects, Gigantic library of 3,300 sounds, Intuitive KAOSS pad for performance, Smart Sound Browser for quick sound selection, Compatible with KORG Gadget

**Features:** Family Sharing

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| M1 Cards Pack | $4.99 | one-time |
| T1 Cards Pack | $4.99 | one-time |

**What reviewers like**

- 👍 Authentic M1 sound reproduction
- 💰 Great value for money
- 🎹 Faithful recreation of the original hardware
- 🎨 Powerful sound customization options
- 🔗 Works well with MIDI controllers

**What reviewers complain about**

- 🐛 Occasional crashes or stability issues
- 🔇 Low output volume compared to other apps
- 🤔 Confusing UI for patch editing and saving
- 🔴 Missing AUv3 support for integration with DAWs

**Reported bugs**

- Disappearing or missing purchased sound cards
- Bluetooth MIDI connectivity issues
- Compatibility problems with certain iOS versions or devices

**Requested features**

- Add AUv3 support for better DAW integration
- Improve preset management and saving capabilities
- Increase master volume control options
- Expand sound library with more cards/expansions


## Frequently asked questions

### Is BK free?

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

### Is KORG iM1 free?

KORG iM1 costs $29.99, and also offers in-app purchases.

### Which has better reviews, BK or KORG iM1?

KORG iM1 is rated higher. BK averages 3.7 out of 5 from 3 ratings, while KORG iM1 averages 4.7 from 1K ratings.

### Do BK or KORG iM1 have ads?

Neither BK nor KORG iM1 shows ads.

### Which is updated more often, BK or KORG iM1?

BK ships an update every 9 months, and KORG iM1 every 7 months. Most recently, BK was updated on October 8, 2026 and KORG iM1 on October 17, 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.*