Comparison

BK Partner vs KORG iM1

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

BK Partner

Control your Roland BK-series instrument's sounds and accompaniments from your iPad. It mirrors the instrument's front panel for quick access to functions, tones, and rhythms. Supports Core MIDI and Roland Wireless Connection.

Highlights
  • Browse and select instrument tones
  • Control musical accompaniments
  • Duplicate instrument's front control panel on iPad
  • Fast visual access to main functions
  • Support for Core MIDI
  • Support for Roland Wireless Connection
Read full description

This software application for iPad let you browse, select, and control the sounds ("Tones") and musical accompaniments ("Rhythms") of your Roland BK-series instrument. When using BK Partner you can: - Play your BK-series instrument while using your iPad as a duplication of its front control panel. This provides fast visual access to the BK's main functions, Tones, and Rhythms. Work with Core MIDI or Roland Wireless Connection (if supported by BK Instrument) *Note: The BK Partner can only display English texts.

About

KORG iM1

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
Read full description

A complete reproduction - and more - of the legendary M1 that defined an era. Mobile Digital Synthesizer for the iPad. ● Selected by Apple as "App Store Best of 2015" ● Ranked #1 on the App Store on Top Paid Music category in more than 20 countries! (15/5/27) Since it went on sale in 1988 the legendary M1 music workstation rapidly achieved record-breaking sales, becoming a mainstay of the music scene from the late 1980s and beyond. The common element of electronic instruments that have left their name in history is that they had a unique sound that was difficult if not impossible to replicate. Sounds such as the “M1 Piano” is instantly recognizable and have appeared on countless hit records over many years, and yet these are sounds that could only be produced by the M1. And that’s what you can now have on your iPad! ● A faithful reproduction of the original M1 Sound The PCM data provides the library of the original M1. For the hardware, we analyzed the circuit diagram of the original design, and completely replicated it in software down to the last detailed parameters. Engineers with an exhaustive knowledge of the M1 made careful adjustments in order to obtain the sound of the original unit, something that cannot be obtained simply by sampling the original sounds. ● A continued evolution of the M1 Not content with simply reproducing the original, iM1 provides further evolutionary developments. Synth parts now have the Filter Resonance that was requested at the time of the original. The effect parts, originally consisting of only two effects, have been powered-up to 18 effects. The user interface has also been refreshed with additions such as a KAOSS pad. iM1 is the ultimate version of the KORG M1. ● A gigantic library encompassing 3,300 sounds and 34 cards* In addition to all 19 of the ROM cards originally released for the M1, iM1 also covers the sounds of the M1EX which expanded the internal PCM of the M1, as well as the sounds of the T-series which appeared as an evolution of the M1. There’s also “BEST OF M1”, a selection of 100 great M1 programs. The new “Smart Sound Browser” makes it quick to find the desired sound. You can also view the sounds ranked by how often they are selected by iM1 users around the world. *with all the expansion card installed via in-app purchase ● KAOSS pad lets anybody perform iM1 features a KAOSS pad from the popular KAOSSILATOR, allowing you to perform intuitively just by touching the screen. By using the dual KAOSS pads to play phrases or adjust the sound, even people who are not accustomed to keyboard instruments or knowledgeable about synthesizers can enjoy performing the iM1. There’s also a conventional keyboard, as well as the “Smart Keyboard”, which lets you specify a scale setting and play phrases with a single finger. ● Use with KORG Gadget for song production iM1 can be used together with Gadget, the music production DAW app that won the App Store Best App of 2014 award in Japan. If both apps are installed, you can use iM1 as a sound module within Gadget, taking advantage of the program sounds in iM1 for music production. iM1 also supports Audiobus and Inter-App Audio, so it can also be used for GarageBand etc. ● Connect a MIDI keyboard and use as a sound module In addition to enjoying iM1 on its own, you can connect a USB MIDI keyboard* via a Lightning adaptor and play the iM1 as an external sound module. You can easily take along an even more powerful workstation sound module as part of your iPad-based compact mobile system. *microKEY, nanoKEY etc. ● Interchangeable with the KORG Legacy Collection and the original M1 Sounds that you create in iM1 can be sent from your iPad via iTunes to a Mac/PC. If you have the Legacy Collection M1, you can use those sounds in a DAW. More info at korg.com

Screenshots

KORG iM14 screens

Verdict

The call

The clearest difference is price: BK Partner at Free against KORG iM1's $29.99. BK Partner also leads on in-app purchases (none vs 2) and iOS requirement (8.1 vs 12.0). KORG iM1's advantage is rating (4.7 vs 4.0) and ratings volume (1K vs 6). On update cadence and ads there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

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

ReceptionRating · Positive reviews · Number of ratings

KORG iM1 holds the better App Store score, 4.7 against 4.0. That said, the two scores are not equally well evidenced: KORG iM1 has 1K ratings behind it against 6, so its average is the more settled of the two. Written reviews point the same way: 61% of BK Partner's written reviews are positive against 82% of KORG iM1's.

UpkeepUpdate frequency

BK Partner ships an update every 12 months, KORG iM1 every 7 months. The most recent releases landed on October 16, 2026 and October 21, 2026 respectively.

Scorecard8 real differences · 2 level
BK Partner versus KORG iM1: the parameters behind the verdict, then further details
ParameterBK PartnerKORG iM1
PriceFree — better$29.99
Rating4.0 (6 ratings)4.7 (1K ratings) — better
Positive reviews60.9% of reviews81.5% of reviews — better
Number of ratings61K — better
Update frequencyEvery 12 monthsEvery 7 months — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPadiPhone, iPad, iPod — better
Requires iOS8.1 — better12.0
Further details — not scored
Size28 MB200 MB
Age rating4+4+
DeveloperRoland CorporationKORG INC.

Customer experience

BK Partner

All ratings6 ratings
Positive66.7%
Neutral16.7%
Negative16.7%
Written reviews23 reviews
Positive60.9%
Neutral13.0%
Negative26.1%

KORG iM1

All ratings1,007 ratings
Positive93.8%
Neutral2.3%
Negative3.9%
Written reviews487 reviews
Positive81.5%
Neutral7.4%
Negative11.1%

Bugs and requests

BK Partner

Not enough reviews yet to summarise bugs or requests.

KORG iM1

Reported bugs

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

Requested features

4 requests
  • 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

In-app purchases

None

BK Partner

No in-app purchases

2 purchases

KORG iM1

One-time2
  • M1 Cards Pack$4.99
  • T1 Cards Pack$4.99

Questions

Is BK Partner free?
BK Partner 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 Partner or KORG iM1?
KORG iM1 is rated higher. BK Partner averages 4.0 out of 5 from 6 ratings, while KORG iM1 averages 4.7 from 1K ratings.
Do BK Partner or KORG iM1 have ads?
Neither BK Partner nor KORG iM1 shows ads.
Which is updated more often, BK Partner or KORG iM1?
BK Partner ships an update every 12 months, and KORG iM1 every 7 months. Most recently, BK Partner was updated on October 16, 2026 and KORG iM1 on October 21, 2026.

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