Comparison

KANTAN Chord vs 4trMTR

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

Head to head
About

KANTAN Chord

This browser extension converts song chords from various websites into numerical "degrees" or Nashville Numbers. It automatically analyzes the song's key and allows users to transpose chords to different formats like Roman numerals or simple numbers.

Highlights
  • Converts chords to Nashville Numbers
  • Displays chords as Roman numerals
  • Automatic key analysis
  • Adjustable analysis sensitivity
  • Supports multiple chord websites
  • Transpose chords to different keys
Features
Read full description

โ€ข Overview KANTAN Chord is a browser extension that converts various chord sites' song chords to its "degrees", also known as Nashville Numbers. (Former name: InstaChordizer) โ€ข Compatible sites - ULTIMATE GUITAR TABS(https://www.ultimate-guitar.com/) - Chordify(https://chordify.net/) - U-ใƒ•ใƒฌใƒƒใƒˆ(https://www.ufret.jp/) - ๆฅฝๅ™จ.me(https://gakufu.gakki.me/) - J-Total Music(https://music.j-total.net/) - Guitarians.com(https://guitarians.com/) - 91่ญœ(https://www.91pu.com.tw/) โ€ข How to use Open the chord web page. From the browser extensions, choose KANTAN Chord icon and it opens a pop-up window. Choose from tabs "C,F,G" (original) , "I,IV,V" (roman numerals), or "1,4,5" (degrees). - "C,F,G" (original) Displays the chords in its original form. Select radio buttons change keys. - "I,IV,V" (roman numerals) Displays the chords' degrees, in standard roman numerals format. - "1,4,5" (degrees) Displays the chords' degrees, in numbers. Different symbols follow the "KANTAN Chord" system, based on the Nashville Number System. For more details, please visit this page: https://instachord.com/instruction/icn/ โ€ข Key analyzation KANTAN Chord automatically analyzes the song's key and displays it in red text with a yellow background banner. When the key changes during a song, it will be displayed with additional banners. E.g. "Key:E(-3)" or "Key:Ab(+1)" Numbers such as (-3) and (+1) represent half steps. If your instrument can transpose, try adjusting to these numbers. If the key analyzation is wrong or is difficult to play, try adjusting the analyzation sensitivity. - Ignore +-5 key changes When changing to a dominant (+5 half steps) or subdominant key (-5 half steps) , chords used will be very similar to its original key. When this option is turned on, KANTAN Chord will ignore +-5 key changes and stay in its original key. โ€ข Displayed keys You can choose keys outside of the auto-analyzed key. - Song's analyzed key The song's auto-analyzed most likely key is outlined in a box. - Difficulty rank The numbers in front of the key (Eg. โ‘ , โ‘ก, โ‘ข...) are difficulty ranks when playing on the InstaChord, from easiest to most difficult. Please use as reference, when the analyzed key if wrong or when the original key is difficult to play. โ‘  and โ‘ก are in bold, and โ‘  is underlined. - Changing they key (in C,F,G tab) When in the C,F,G tab, you can pick different keys to transpose to. - Changing they key (in I,IV,V or 1,4,5 tab) In I,IV,V or 1,4,5 tab, you can change the base key. Apply when the analyzed key is wrong, or when the original key is difficult to play. If other keys are greyed-out, turn off analyzation sensitivity. โ€ข Options for C,F,G tab - Disable automatic loading KANTAN Chord will not take effect until the icon is pressed. Use this option if there are compatibility issues with the site's features or other extensions. This option is only effective in the C,F,G tab. - Hide key display KANTAN Chord displays the song's key and displays it in red text with a yellow background banner. Use this option to hide the key display. This option is only effective in the C,F,G tab. โ€ข Options for I,IV,V tab - b โ†’ # All half tones are represented with # - IIm, VIm โ†’ ii, vi Minor chords are represented with lower case roman numerals. โ€ข Options for 1,4,5 tab - 3b/7b โ†’ 8/9 (5b/2b โ†’ 8/9 for minor key) For the InstaChord, commonly used chords are allocated on the 8 and 9 buttons. Using this option will make use of these buttons. - Use minor key Allows the use of minor key โ€ข Beginner mode By selecting LV.0 / LV.1 / LV.2 shown on the first line, you can adjust the difficulty of the chords. In LV.0 / LV.1 mode, chords will be simplified. In LV.2 mode, all chords will be in their original form. This mode isl not available when minor key is selected.

About

4trMTR

Transform your iPhone into a straightforward multi-track recorder for music creation. Easily layer guitar, vocals, bass, and more, one track at a time. Perfect for capturing song ideas or creating band demos without complex software.

Highlights
  • 4-track multi-track recording
  • Punch-in re-recording
  • Selectable audio input
  • Project saving and management
  • Simple, immediate recording interface
Features
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iPhone into a simple 4-track MTR. 4trMTR is a simple multi-track recorder that can record guitar, bass, vocals, etc. one track at a time. When you come up with an idea for a song. When you want to make a demo of the band. When you want to record musical instruments and songs. You can start recording on your iPhone right away without having to launch a complicated DAW. [Simple 4-track recording] You can use 4 tracks to record performances and songs on top of each other. For example, Track 1: Guitar Track 2: Vocals Track 3: Bass Track 4: Chorus You can use it like this. [Punch-in recording] You can re-record by specifying only the part you want to re-record. Even if you want to modify a part of the performance, you don't have to re-record everything from the beginning. [Select input and record] You can choose the input to use for recording from the available inputs. You can easily record with just your iPhone, or you can use it for recording using compatible external audio devices. [Save as a project] The recorded content can be managed as a project. You can leave your song ideas and demos and record them later. [Because it's simple, you can record it right away] The first recording was a cassette. It didn't have much function, but I felt like I could make anything. 4trMTR is an app for reproducing the fun of such simple recording on iPhone. Rather than learning a lot of functions, record first. Hold the instrument, press the REC, and stack the sound. Try to leave your song ideas on 4trMTR.

Screenshots

KANTAN Chord4 screens
4trMTR3 screens

Verdict

The call

The clearest difference is review sentiment: 4trMTR at 100% against KANTAN Chord's 40%. 4trMTR also leads on update cadence (every 3 weeks vs every 2 months). KANTAN Chord's advantage is price (Free vs $1.99) and device support (4 vs 2). On ads and in-app purchases there is nothing between them.

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

CostPrice ยท In-app purchases ยท Ads ยท Monetization

KANTAN Chord is free to download; 4trMTR costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

KANTAN Chord ships an update every 2 months, 4trMTR every 3 weeks. Both last shipped on November 12, 2026.

Scorecard6 real differences ยท 2 level
KANTAN Chord versus 4trMTR: the parameters behind the verdict, then further details
ParameterKANTAN Chord4trMTR
PriceFree โ€” better$1.99
Positive reviews40.0% of reviews100.0% of reviews โ€” better
Update frequencyEvery 2 monthsEvery 3 weeks โ€” better
AdsNoNo
In-app purchasesNoNo
MonetizationFree โ€” betterPaid
DevicesiPhone, iPad, iPod, Mac โ€” betteriPhone, iPad
Requires iOS15.0 โ€” better17.6
Further details โ€” not scored
Size1 MB12 MB
Age rating4+4+
DeveloperInstaChord Corp.YUKIO TOKIWA

Customer experience

KANTAN Chord

Written reviews5 reviews
Positive40.0%
Neutral0.0%
Negative60.0%

4trMTR

Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

KANTAN Chord

No in-app purchases

None

4trMTR

No in-app purchases

Questions

Is KANTAN Chord free?
KANTAN Chord is free to download, with no in-app purchases.
Is 4trMTR free?
4trMTR costs $1.99, with no in-app purchases.
Do KANTAN Chord or 4trMTR have ads?
Neither KANTAN Chord nor 4trMTR shows ads.
Which is updated more often, KANTAN Chord or 4trMTR?
KANTAN Chord ships an update every 2 months, and 4trMTR every 3 weeks. Most recently, KANTAN Chord was updated on November 12, 2026 and 4trMTR on November 12, 2026.

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