GTK Player's Toolkit Get the app

GTK · Guitar

GTK – Guitar Player's Toolkit

Tools for your guitar journey.

The original GTK. Built by a guitarist to connect music theory to the fretboard – not a theory course, but the tools that show you where the theory lives under your fingers.

Download on theApp Store See all tools
  • $9.99 one-time
  • Version 1.7.6
  • 67.2 MB
  • iPhone · iPad · Mac (Apple silicon)
E G × C E C
C major, open position

Highlights

Made for guitar players

Chord Master

Around 3,600 chords, custom voicings, name-from-notes lookup and playback in steel, nylon or classical tones.

Triad Practice & Positions

Learn triads across string sets and inversions, and map triad positions through a chord progression.

Scales & Scale Sharing

Compare up to four scales on one neck, with diatonic chords and triads for every key.

24-fret fretboards

Full-length scrolling necks with selectable skins and marker colours.

Inside the app

See it in action

Chord Master on guitar with the Library tab selected. Dm is typed in the search box, with a count of 32. Chord diagrams for Dm, Dm/A, Dm/Ab, Dm/B, Dm/Bb and Dm/C are shown, each with a play button, a heart, an arpeggio button and a copy button.
Library: search for a chord and see how to play it.Chord Master guide
Chord Library on guitar, the All tab with an empty search box and a count of 1,174 chords. Chord diagrams for A, A/Ab, A/B, A/Bb, A/C and A/C♯ are shown in a grid, each with a play button, a heart, finger numbers and the note under each string.
The All tab: 1,174 chord diagrams, each ready to play.Chord Library guide
Edit Chord on guitar: frets 3, 2 and 1 on the G, B and high e strings with the low strings muted, named My Custom A♯m, with its chord diagram and play button.
A♯m on the top three strings, named and ready to save.Custom Chords guide
Chord Build on guitar with the notes C, E and G switched on in red, green and blue. The name C is shown large, with Em3 and GP4 listed as alternatives at 67%. The fretboard shows every C, E and G from the open strings to fret 6.
Select C, E and G: GTK names the chord C and marks every one of those notes on the neck.Chord Build guide
Chord Explore on guitar. A table lists the notes placed on strings 1 to 5: F♯ at fret 2, D at fret 3, A at fret 2, and open D and A. The sixth string is muted, with a red X. The name D is shown large, with D/A at 100% and AP4 at 67% as alternatives.
Tap the fretboard: GTK names the shape you are holding, D, with D/A as an alternative.Chord Explore guide
Chord Transposer with Actual Key C, Desired Key G and Capo on Fret 0. In the Chord Progression list, Instead of Cm, Dm, E7, E, G and Am becomes Play Gm, Am, B7, B, D and Em; the Capo column is empty and Effective matches Play.
C to G, no capo: Cm, Dm, E7, E, G, Am become Gm, Am, B7, B, D, Em.Chord Transposer guide
Scales on guitar set to the C major scale: the notes C, D, E, F, G, A and B with scale degrees 1 to 7, and their positions on the fretboard as colour-coded note names.
C major across the neck, with its notes and scale degrees.Scales guide
Scale Sharing on guitar with four scales listed: C Major (blue) and A Minor (green) switched on, F Major and G Major switched off. The fretboard shows each note in one of the two colours, with dots split into blue and green pie slices where the scales share a note.
C major and A minor: the same seven notes, so every dot is shared.Scale Sharing guide
Triad Sharing on guitar, the Triads tab, with only C (blue) switched on and only the 123 string-set box ticked; 234, 345 and 456 are unticked. The fretboard from fret 4 shows the notes C, E and G as blue dots on the top three strings only (high E, B and G); the lower three strings are empty.
One string set: with only 123 ticked, C’s triad appears on the top three strings alone.Triad Sharing guide
Chord Sharing on guitar, the Chords tab, with a box for entering a chord name and four chords listed: Daug9 (D, F♯, A♯, C, E), D7, Am7 and Emaj7. Only Daug9 (blue) is switched on. Its notes are shown across the fretboard from fret 3, with the root D ringed.
Type a chord name, even an unusual one like Daug9: its notes across the neck, root ringed.Chord Sharing guide
Position Finder on guitar set to the key of G major at fret 5: the notes G, A, B, C, D, E and F♯, with their positions on the fretboard from fret 3 to 10 and coloured rings marking groups of notes to improvise around.
Song moves to G: its notes around fret 5, with rings to improvise in.Position Finder guide
Circle of Fifths with Key C and Mode Ionian. C is blue at the top of the wheel, F is red on its left and G is green on its right, with Am, Dm, Em and B° shaded inside. The centre of the wheel is empty because C has no sharps or flats. Below, Diatonic Chords in C Ionian lists I C, ii Dm, iii Em, IV F, V G, vi Am and vii° B° with the notes of each chord.
C Ionian: C major, with F and G either side and no sharps or flats.Circle of Fifths guide
Mode Converter turning C Dorian into D Phrygian, up 2 semitones, with the colour-coded notes and scale degrees of both modes.
C Dorian to D Phrygian: same notes, new home, up 2 semitones.Mode Converter guide
Note Practice on guitar asking for the note D on string 1, with the answer shown at fret 10 on the high E string and a timer counting down.
String 1, note D: fret 10 on the high E string.Note Practice guide
Triad Practice showing C minor in root position on the E, B and G strings at fret 3: the notes C, D♯ and G as coloured pills and on the fretboard.
C minor, root position, on the E, B and G strings at fret 3.Triad Practice guide
Tuner showing C♯ at 140.0 Hz, 17.1 cents sharp, on the needle gauge.
Needle gauge, cents offset and Hz readout.Tuner guide
Metronome at 120 BPM with four beats per measure, preset tempos, tap tempo and the current beat highlighted.
Set the tempo, tap it in, or pick a preset.Metronome guide

Everything included

17 tools, one app

Chords

Theory

Practice

Utilities

Tunings & fretboard

Fits your instrument

Chords
~3,600 chords
Scales
80+ scales in 14 categories
Frets
Up to 24
  • StandardE A D G B E
  • Drop DD A D G B E
  • DADGADD A D G A D
  • Drop CC G C F A D
  • Open GD G D G B D
  • Open DD A D F♯ A D
  • Half step downE♭ A♭ D♭ G♭ B♭ E♭
  • Whole step downD G C F A D

What's new in 1.7.6

  • Position Finder follows the selected tuning and reaches fret 24.
  • Flat keys are now spelled correctly in Position Finder.
  • Refreshed app icon and splash screen.
Full version history on the App Store →
  • One-time purchaseNo subscriptions, no in-app purchases, no ads.
  • Works offlineEverything runs on your device. No account, no internet needed.
  • No data collectedAudio for the tuner is processed on-device and never recorded or sent.
  • Family SharingBuy once and share with up to six family members.
Download on theApp Store Questions? Read the FAQ

The family

Play more than one?

v1.3.2

Ukulele

Tools for your ukulele journey

Chords
4,200+ voicings
Tunings
4
Explore & Buy
v1.3.3

Banjo

Tools for your banjo journey

Chords
10,000+ chord entries
Tunings
8
Explore & Buy
Coming soon

Bass

Tools for your bass journey

Chords
582 chords
Tunings
9
Explore Bass