What is ScaleDr?
ScaleDr is a play-along practice tool for musicians. Pick a scale, chord quality, or exercise, set a tempo, and play along with your instrument or voice. Use it to work through all 12 keys systematically — the Progression feature cycles roots automatically so you can stay focused on the music, not the app.
Tabs
Scale — Play ascending and descending scale runs in the selected key and mode. The Pattern chip controls direction (Up, Down, Up/Down, Down/Up).
Arpeggio — Play any chord quality from the Quality dropdown — 25 qualities from triads through 13ths. The chord symbol updates with the root; the Pattern chip controls direction. Family and Mode are inactive here since Quality drives the arpeggio directly.
Intervals — Play intervals through the selected scale. The Mode chip toggles between Diatonic (3rds, 4ths, 5ths, 6ths, 7ths walking the scale's degrees) and Chromatic (fixed interval classes — min 2nd, Maj 3rd, P5, etc. — applied to every chromatic step from the root, independent of the parent scale). The Interval pair chip controls each individual pair's direction (low-to-high or high-to-low); the Scale Walk chip controls the order in which the scale's degrees are visited (Up, Down, Up/Down, Down/Up).
Exercises — Structured patterns: diatonic triads and 7th-chord sequences (1-3-5-7 orderings, with a Quality picker for cross-quality cycling), scale-and-chord combos, modal practice (Bright → Dark through all seven Major modes), tetrachord studies (Bright → Dark through eight tetrachord qualities — Lydian, Ionian, Dorian, Phrygian, Hungarian Major, Hungarian Minor, Harmonic, Spanish Phrygian), and arpeggio chord sequences. Pick an exercise from the dropdown; tap ⓘ for a description of the selected exercise.
Main controls
Root / Scale / Mode chips (top bar) — Set the tonal material for every tab. Changing them instantly rebuilds the notation and note strip.
↻ Reset (top bar) — Snaps the app back to a clean starting state: C Major Ionian on the Scale tab, BPM 120, all toggles off. Use it any time you feel stuck in stacked option states. An Undo reset? bubble appears for 5 seconds after each reset in case you tapped by accident.
Tempo — Drag the slider or type a BPM value. Changes take effect at the next Start.
Drone — Holds a sustained root tone underneath your practice note. Good for intonation work.
Chord Pad — Plays the current chord quality as a background pad. Useful for harmonic context on the Arpeggio tab.
Keys — How many root changes the Progression cycles through before stopping (or looping). Default 12 = all 12 keys.
Loop — Repeats the current exercise or scale run without stopping. Combine with Progression to drill all keys continuously.
Octaves — How many octaves the scale or arpeggio spans. More octaves means longer phrases before cycling.
Progression
When Progression is on, each time you press Start the root advances by the selected interval (Cycle of 4ths, Cycle of 5ths, Chromatic Up, or Chromatic Down). After the number of keys set in the Keys field, playback stops — or loops back to the first key if Loop is also on. The count-off (if enabled in Setup) plays before each new key.
Tip: set Keys to 12 and Loop on to drill an exercise through all 12 keys without stopping.
Setup drawer
Transposition — Sets concert (C), Bb (trumpet, tenor sax, clarinet), Eb (alto sax, baritone sax), or F (French horn, English horn) transposition. The notation and note names shift so you read your instrument's written pitch.
Clef — Treble or Bass. Switches the notation staff; does not affect playback pitch.
Count-off — A metronome intro before playback starts. 4 beats or 2 beats, selectable. The same count-off plays between keys when Progression is on.
Playback voice — Pure (sine), Mellow (triangle), Reed (sax/oboe timbre), or Pluck (guitar/piano timbre). Affects the practice note sound only.
Chromatic enrichment — Inserts chromatic embellishment notes around each target tone: Approach adds a half-step approach before each note; Enclosure adds a half-step above + below before each note. Off by default. Useful for jazz-language ear training and bebop-style chromatic articulations.
Greyed-out chips
When a chip is greyed out, it means the current combination of tab + scale + exercise doesn't use that control. Tap a greyed chip for a brief explanation of why it's inactive and how to re-enable it (for example, on Intervals + Chromatic mode the Family and Mode chips are greyed and tell you to switch Mode back to Diatonic if you want scale-based intervals again).
If multiple chips are greyed and you feel stuck, tap the ↻ Reset icon in the top bar to return to a clean starting state — much faster than untangling the path that got you there.
Tips
The count-off tempo matches the BPM slider — so a 4-beat count-off at 120 BPM gives you exactly one bar before the first note.
The Search icon (🔍) in the top bar lets you jump directly to any scale, mode, or chord quality by name. Try "Lydian", "Bb dorian", "Cmaj7", or just a root like "Eb". Shortcuts: # or + for sharp, - for flat.
The per-exercise ⓘ button next to the Exercise dropdown describes exactly what the currently-selected exercise does — this Help overlay covers general app usage.
Install ScaleDr to your phone home screen so it works offline and runs full-screen: on iPhone/iPad open in Safari, tap the Share icon, then Add to Home Screen. On Android Chrome, tap the menu, then Install app.
Credits
With special thanks to David Baker, Gary Campbell, Jerry Coker, Dan Haerle, Gary Keller, Ron Miller, Herb Pomeroy, George Russell, and Dimitri Tymoczko — the pedagogy this app draws on stands on their work.