Features Built for Real Practice

Live key and chord detection, interactive Circle of Fifths, seven visualization modes, multi-instrument chord charts, a tunes library with ABC notation, lyrics, audio looping, recording, and essential practice tools—all in one offline app.

Core Features

Real-time detection and practice tools that work 100% offline. No accounts, no ads, no subscriptions.

🎼 ABC Sheet Viewer & Editor

Type or paste ABC, or import your own collections—clean notation renders instantly. Transpose visually, toggle tablature layers (guitar, mandolin, ukulele), print PNGs, and keep charts side by side with lyrics and notes.

🎧 Live Key & Chord Detection

Jam with anything—phone speaker, Bluetooth, or room audio. The Circle of Fifths, Nashville numbers, chord confidence, and bass-aware detection stay in sync as you play.

🔮 Next‑Chord Prediction

See four likely chords, complete with the correct fingering chart for your chosen instrument. Lock a key, swap tunings, and keep the progression moving.

🎵 Audio Player, Loops & Recorder

Attach your own tracks, slow them down without changing pitch, save named loops, and capture fresh ideas with the built-in recorder.

🎨 Customize Your Experience

Multiple themes & custom color schemes, adjustable interval colors, per-window focus layouts, and detection thresholds you can dial in for your room.

🧪 Why I built this

I’m a data scientist (business analytics background) who normally writes R and Python. I wanted to learn Kotlin and mandolin at the same time, so I started gluing together the tools I kept wishing existed while practicing.

I have twin boys, so most of this ships after bedtime or in the cracks between work and life. I’m also taking a bluegrass mandolin class at the Frank Hamilton School in Decatur, GA, which keeps exposing rough spots in my ear and timing.

I test JamBuddy at local jams: I’ll hear a tune I don’t know, pull a quick ABC via search, drop it into a collection, and lean on the Circle of Fifths panel when my ear blanks on the change.

No ads. No accounts. Just a one‑time purchase and incremental improvements when I can earn them. If you end up using it and something feels off, send a note—those usually become the next build.