Comparison

KORG cortosia vs IMSLP

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

Head to head
About

KORG cortosia

This app helps musicians improve their sound quality by analyzing five key elements of performance in real-time. It provides instant feedback, tracks daily progress, and allows users to compare their skills globally. Ideal for beginners and intermediate players seeking to refine their technique.

Highlights
  • Real-time analysis of five 'good sound' elements
  • Instant scoring on a 100-point scale
  • Daily practice recording and progress tracking
  • Global ranking for 'good sound' competition
  • Supports multiple wind and string instruments
  • Model tone comparison
Read full description

KORG cortosia, the tuner app that makes it enjoyable to practice the basics Learn “good sound” and enjoy “good performance”! *This app can evaluate only flute, clarinet, trumpet, violin, cello, saxophone, trombone and euphonium performances. (Operating Requirements) iOS8 or later iPhone 5 or later, iPod Touch 5th Generation or later KORG has answered the question: “Can a tuner recognize good sound?” With the KORG cortosia you'll see what's missing from “good sound” with just a glance. Even practice that's slightly boring (such as practicing the production of single notes) will become enjoyable. The cortosia is a completely new type of interactive tuner app designed to improve the overall quality of sound produced by the artist. * Analyzes five elements of “good sound” and rates them in real time * Automatically records “good sound” so you can check your daily improvement in technique * Lets you compete against the world in “good sound” and vie for ranking * Supports flute, clarinet, trumpet, violin, cello, saxophone, trombone and euphonium Analyze five elements of “good sound” and rate them in real time: Just what is “good sound”? Beautiful sound, pleasant sound, sound that resonates in the listener's heart. Perceptions of “good sound” differ between people, but could there be some commonalities? Through cooperative research with Pompeu Fabra University in Barcelona, Spain, under the direction of Professor Xavier Serra, Korg has arrived at a technology “Artistry” (*1) for evaluating “good sound” based on five elements. 1: Pitch Stability 2: Dynamic Stability 3: Timbre Stability 4: Timbre Richness 5: Attack Clarity Simultaneously with the tuner display, a radar chart shows the results of analyzing these five elements in real time, and scores them on a scale of 100 points. While tuning, you can see at a glance what aspects of your tone are lacking. You can also listen to a model tone and hear how it differs from your own sound. This is highly recommended for beginners who have just started a musical instrument, as well as for intermediate players who want to advance to the next level. *1: Automatic Rating Technology for musical InSTRument plaYers Automatically record “good sound,” and check your daily advances in technique: Data is automatically recorded and kept when tuning and scoring. You can audition the accumulated recording data or recall a radar chart for it, and you can also check the number of hours you practiced and your best score for each day. By looking at your past results, you can see how you are progressing. In addition, you can post your score to a social networking service such as Facebook or Twitter allowing you to record or upload your daily progress (or backsliding) as if you were writing a diary. Whether you use this to compete with your friends or to give encouraging comments, it's a great way to improve your skill while enjoyably sharing information. Compete with the world for “good sound”: Your ranking is compiled by averaging your highest score for each note, and displayed. You'll be able to see your current position among performers around the world who use cortosia. Supports flute, clarinet, trumpet, violin, cello, saxophone, trombone and euphonium. A full range of basic functionality including tuner, metronome, and level meter: In addition to a chromatic tuner that benefits from Korg's forty years of know-how in tuner development, there's a metronome that supports tap tempo, and even a level meter, making cortosia a great partner for performance or practice.

About

IMSLP

Access a vast digital library of classical music scores on your iOS device. Enjoy full access to commercial recordings, instant downloads, and new uploads with a membership subscription. Support the music community while exploring a comprehensive collection.

Highlights
  • Browse IMSLP/Petrucci Music Library
  • View musical scores
  • Access commercial recordings
  • Instant downloads
  • Access new uploads instantly
  • Membership subscription benefits
Features
Read full description

Browse IMSLP/Petrucci Music Library and view scores from the comfort of your iOS device. IMSLP Membership Subscription Length of subscription: 1 month. Benefits include: • Full access to commercial recordings • Access all features in this app • No waiting for downloads • Access new uploads instantly • Knowing that you helped keep IMSLP running and serving the music community Payment will be charged to iTunes Account at confirmation of purchase. Subscription automatically renews unless auto-renew is turned off at least 24-hours before the end of the current period. Account will be charged for renewal within 24-hours prior to the end of the current period, and identify the cost of the renewal. Subscriptions may be managed by the user and auto-renewal may be turned off by going to the user’s Account Settings after purchase. Any unused portion of a free trial period, if offered, will be forfeited when the user purchases a subscription to that publication, where applicable. Terms of Service and Privacy policy - https://imslp.org/wiki/IMSLP:Terms_of_Service_and_Privacy_policy_(app)

Screenshots

KORG cortosia4 screens
IMSLP4 screens

Verdict

The call

The clearest difference is price: IMSLP at Free against KORG cortosia's $9.99. IMSLP also leads on rating (4.6 vs 4.2) and update cadence (every 10 days vs every 2 months). KORG cortosia's advantage is in-app purchases (none vs 1). On ads, device support and iOS requirement 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

IMSLP is free to download; KORG cortosia costs $9.99 up front. IMSLP sells 1 in-app purchase, starting at $3.99 per month. KORG cortosia asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

IMSLP holds the better App Store score, 4.6 against 4.2. That said, the two scores are not equally well evidenced: IMSLP has 514 ratings behind it against 6, so its average is the more settled of the two. Written reviews point the same way: 48% of KORG cortosia's written reviews are positive against 70% of IMSLP's.

UpkeepUpdate frequency

KORG cortosia ships an update every 2 months, IMSLP every 10 days. The most recent releases landed on October 30, 2026 and October 29, 2026 respectively.

Scorecard7 real differences · 3 level
KORG cortosia versus IMSLP: the parameters behind the verdict, then further details
ParameterKORG cortosiaIMSLP
Price$9.99Free — better
Rating4.2 (6 ratings)4.6 (514 ratings) — better
Positive reviews47.8% of reviews70.1% of reviews — better
Number of ratings6514 — better
Update frequencyEvery 2 monthsEvery 10 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaidFreemium — better
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS12.0 — better13.0
Further details — not scored
Size35 MB232 MB
Age rating12+4+
DeveloperKORG INC.Project Petrucci LLC

Customer experience

KORG cortosia

All ratings6 ratings
Positive66.7%
Neutral16.7%
Negative16.7%
Written reviews23 reviews
Positive47.8%
Neutral26.1%
Negative26.1%

IMSLP

All ratings507 ratings
Positive88.4%
Neutral3.7%
Negative7.9%
Written reviews298 reviews
Positive70.1%
Neutral11.4%
Negative18.5%

Bugs and requests

KORG cortosia

Not enough reviews yet to summarise bugs or requests.

IMSLP

Reported bugs

6 issues
  • Crashes when opening scores
  • Scores disappearing from library
  • Login issues and lost data
  • Incompatibility with older devices after updates
  • Annotation issues causing loss of data
Show 1 more
  • Inability to edit file information after import

Requested features

11 requests
  • Predictive text for score annotations
  • Ability to restore original zoom settings
  • Metric to indicate device performance during page turns
  • Folder-like organization system
  • Color wheel and custom pen/highlighter options
Show 6 more
  • Ability to rename music files
  • Different color folder options
  • Split view support
  • Easier way to import scores from other sources
  • Instrumentation information for scores
  • Sorting by instrumentation

In-app purchases

None

KORG cortosia

No in-app purchases

1 purchases

IMSLP

Subscriptions1
  • Membership Subscription$3.991 Month

Questions

Is KORG cortosia free?
KORG cortosia costs $9.99, with no in-app purchases.
Is IMSLP free?
IMSLP is free to download, with in-app purchases available.
Which has better reviews, KORG cortosia or IMSLP?
IMSLP is rated higher. KORG cortosia averages 4.2 out of 5 from 6 ratings, while IMSLP averages 4.6 from 514 ratings.
Do KORG cortosia or IMSLP have ads?
Neither KORG cortosia nor IMSLP shows ads.
Which is updated more often, KORG cortosia or IMSLP?
KORG cortosia ships an update every 2 months, and IMSLP every 10 days. Most recently, KORG cortosia was updated on October 30, 2026 and IMSLP on October 29, 2026.

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