Bellows Accordion

Bellows Accordion turns a foldable iPhone into a squeezebox. Hold the open phone like a handheld game console with a thumb on each pane: the left pane has bass and chord buttons, the right pane has melody keys, and the hinge between them is the bellows. Opening and closing the phone fills the bellows with air, and the air drives the loudness and brightness of the reeds. Small, slow movements are enough: the bellows keep a little air in reserve, so a gentle stroke sustains a phrase and changing direction does not drop the sound. Hold the phone still and the sound fades, the way a real instrument does when the player stops. The first time you open the phone, the bellows breathe a chord and a short note shows you how to play. If you press keys without moving the bellows, the gauge pulses to remind you to pump. Everything is sized for thumbs. The melody keys run down the right pane like the keyboard of a piano accordion, low notes at the top, up to twelve white keys at a time with buttons to move up or down an octave. The bass buttons run down the left pane around the circle of fifths, with bass notes, major chords and minor chords, each labelled with its root and chord. Bass buttons sound their note with the octave above. The AIR knob gives a steady breath when you tap it, for playing on a table or giving your hands a rest. Hold it to open the air valve and move the bellows silently. Three instruments share one synthesiser. Choose one with the three register tabs; each plays a short chord so you hear the difference, and your choice is remembered. Accordion uses a musette, three-reed set. Harmonica is bisonoric: pulling plays a whole tone higher, and every key shows both of its notes, lighting the one that will sound. Harmonium is slow and droning and keeps singing after you stop, as if pumped into a reservoir. Each instrument has its own finish: ruby pearloid, graphite and walnut. The sound is made on the device by a twelve-voice synthesiser with the breath of the bellows, a soft key click, a stereo spread and a warm room. Audio is set up for low latency and mixes with other apps, so you can play along with a backing track. The songbook has six traditional tunes: Ode to Joy, Oh! Susanna, Frère Jacques, Twinkle Twinkle, When the Saints and Clementine. The next key lights up and waits for you, the next chord and bass button glow, and harmonica tunes tell you when to push and when to pull. Tap play to hear a tune first. You can record your playing. The REC button captures the screen and the instrument's sound as a take. Recording starts only when you tap it and ends when you stop, close the phone or show the cover. iOS then shows its own preview, where you choose to save the video to Photos or share it; close it without either and Bellows asks before the take is thrown away. Bellows keeps no copy and uploads nothing. When the phone is closed, the outer screen shows the three instruments as cards: swipe to choose one, tap a card to hear it, and open the phone to play. Bellows also works on any iPhone. Hold it sideways, even with rotation lock on. Tap AIR for a steady breath, rock the phone toward you and away, or drag up and down on the bellows strip between the panes. On a foldable iPhone both thumbs stay free for bass and melody while the hinge pumps the air. Options include a mirrored layout for left-handed players. VoiceOver users can play the keys and buttons directly, with every key and chord named. Bellows is private by design: no accounts, no analytics, no advertising and no network calls. Bellows never uses the microphone. It is a one-time purchase with no subscriptions. Limits: no MIDI, no tuner, and the outer screen of a closed foldable iPhone shows the instrument cards rather than a playable instrument. The bass board covers up to eight roots with bass, major and minor rows, a subset of a full accordion.