What this is
Swing Time turns a phone into half of a two-person handbell choir. One octave (do–re–mi–fa–sol–la–ti–do) is split into two four-note tetrachords. Each phone plays one tetrachord by detecting swing gestures with the motion sensors — no pairing or syncing between phones required.
How to hold the phone
Hold the phone like a hatchet or hammer, gripped sideways rather than upright like you're reading it:
- Right-handed: the screen's left edge points down.
- Left-handed: mirrored — the screen's right edge points down.
Set the matching option in the Hand selector on the Play screen — it's what tells the app which physical direction counts as "up" versus "down."
The four motions
- Down — chop the phone sharply downward.
- Up — swing it back up.
- Left / Right — swing sideways. Left-handed: screen leading is Left, back leading is Right. Right-handed: mirrored — screen leading is Right, back leading is Left.
Each motion always rings the same note slot, regardless of hand:
| Motion | Lower | Upper |
|---|---|---|
| Down | Do | Sol |
| Up | Re | La |
| Left | Mi | Ti |
| Right | Fa | Do |
Play screen controls
- Hand — Right-handed or Left-handed. Must match your actual grip.
- Tetrachord — Lower or Upper. Picks which half of the octave you're playing.
- Note chips (Down/Up/Left/Right, showing the current note names) — tap one to ring that note directly, without swinging. Handy for checking your notes before playing.
- Enable Motion / Stop Motion — turns gesture detection on or off. Tap Stop Motion any time to silence the phone without leaving the page.
You don't need to watch the screen while playing — the app is designed to be used by feel while reading a paper score.
If gestures misfire
Open the Debug screen for a live sensor readout, a log of detected gestures, and sliders to adjust the sensitivity thresholds without editing any code.