| name | p5-phone |
| description | Use when generating p5-phone examples or answering questions about p5-phone APIs: mobile sensors, device orientation, accelerometer, gyroscope, touch, microphone, p5.sound, speech recognition, PhoneCamera, ML5 camera mapping, vibration, torch/flashlight, NFC, Bluetooth BLE, GPS/geolocation, geoDistance/geoInPolygon, lockGestures, enablePermissionsTap, enableHardwareTap, arbitrary hardware combinations, mobile browser permissions, p5.js 2 compatibility. |
| argument-hint | Describe the p5-phone example or API question |
p5-phone: Mobile Hardware for p5.js
p5-phone is a single-file helper library that gives p5.js sketches access to mobile phone hardware — motion sensors, microphone, sound, speech, camera (with ML5 coordinate mapping), vibration, torch/flashlight, NFC, GPS/geolocation, and Bluetooth LE — plus mobile gesture locking, browser-permission activation UI, and an on-screen debug console. Current version: 1.13.0.
It works in both p5.js 1.x and 2.x (auto-detected at runtime). Every public function is attached to window (global mode) and mirrored on p5.prototype (instance mode), so you call them as bare globals like lockGestures() and enableSensorTap().
Pair this with the p5js-2x skill. p5-phone only unlocks the hardware and hands you p5's own globals and objects; the p5.js 2.x language patterns around them (async asset loading, the unified pointer/touch model, renamed APIs) live in the p5js-2x skill. Load both when writing phone sketches — and read the next section before writing any hardware code.
When to use this skill
Use it whenever the request involves a p5-phone sketch, mobile p5.js hardware interaction, or an explanation of how p5-phone works: device orientation / accelerometer / gyroscope, touch, microphone / p5.sound, speech recognition, PhoneCamera and ML5 mapping, vibration, torch/flashlight, NFC, GPS/geolocation (geoRead, geoDistance, geoInPolygon), Bluetooth BLE, lockGestures, enablePermissionsTap / enableHardwareTap, arbitrary hardware combinations, mobile browser permissions, or p5.js 2 compatibility.
Quick Start
For generated examples, produce a complete index.html and sketch.js unless the user asks for a single file or snippet.
HTML baseline (p5.js 2-compatible):
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Mobile p5.js App</title>
<style>
body { margin: 0; padding: 0; overflow: hidden; }
</style>
<script src="https://cdn.jsdelivr.net/npm/p5@2.2.3/lib/p5.js"></script>
<script src="https://cdn.jsdelivr.net/npm/p5.js-compatibility@0.2.0/src/preload.js"></script>
<script src="https://cdn.jsdelivr.net/npm/p5-phone@1.12.1/dist/p5-phone.min.js"></script>
</head>
<body>
<script src="sketch.js"></script>
</body>
</html>
Add p5.sound only when the sketch uses microphone levels, oscillators, audio input, sound output, or speech. Place it after p5 and before p5-phone/sketch.js:
<script src="https://cdn.jsdelivr.net/npm/p5.sound@0.3.0/dist/p5.sound.min.js"></script>
Minimal sketch (sketch.js):
function setup() {
createCanvas(windowWidth, windowHeight);
lockGestures();
enableSensorTap('Tap to enable motion sensors');
}
function draw() {
background(20);
if (!window.sensorsEnabled) {
fill(255);
textAlign(CENTER, CENTER);
text('Waiting for sensors', width / 2, height / 2);
return;
}
fill(0, 180, 255);
circle(width / 2 + rotationY * 4, height / 2 + rotationX * 4, 80);
}
function mousePressed() {
return false;
}
Golden Rules
- Call
lockGestures() in every mobile sketch setup(). It blocks pull-to-refresh, swipe-back, pinch-zoom, double-tap zoom, long-press menus, and overscroll so the canvas behaves like an app.
- Request every permission from a user gesture. iOS grants sensitive APIs only during transient user activation (a tap/click). Never auto-request on page load — use an
enable* activation UI.
- Gate all hardware reads behind the matching
window.*Enabled flag (sensorsEnabled, micEnabled, bleConnected, etc.). Reading before permission returns stale/undefined data.
- Use
mousePressed / mouseDragged / mouseReleased, not p5 1.x touchStarted / touchMoved / touchEnded. The mouse callbacks fire for both mouse and touch in p5.js 1.x and 2.x; the touch callbacks are removed/no-ops in p5.js 2.
- Serve over HTTPS (or
localhost). Sensors, mic, camera, NFC, BLE, GPS, and torch all require a secure context on mobile.
- Need several hardware features from one tap? Use a single combined call —
enablePermissionsTap(['sensors', 'torch']) — not several single-permission binds on the same gesture. One call keeps iOS transient activation intact and fires userSetupComplete() once.
- Use exactly one activation style per permission need unless the user explicitly asks to compare styles.
Use p5.js built-ins — do not reimplement them
The most common failure mode is a model hand-rolling hardware plumbing (a raw DeviceOrientationEvent listener, a touchstart handler, a Web Audio graph, a manual asset loader) instead of reading the values p5-phone and p5.js already provide. p5-phone deliberately surfaces everything through p5's own globals and objects. For each concern below, use the p5 built-in — never a bespoke equivalent:
| p5-phone concern | Use these p5.js built-ins (not custom code) | Notes |
|---|
| Device orientation | rotationX, rotationY, rotationZ (+ pRotationX/Y/Z) | p5 globals; p5-phone only gates them via sensorsEnabled |
| Acceleration | accelerationX/Y/Z, pAccelerationX/Y/Z | p5 globals |
| Rotation rate | rotationRateAlpha, rotationRateBeta, rotationRateGamma | p5 globals |
| Motion events / thresholds | deviceMoved(), deviceShaken(), setMoveThreshold(), setShakeThreshold(), deviceOrientation | define the callbacks as globals |
| Touch / pointer input | mousePressed(), mouseDragged(), mouseReleased(), mouseX, mouseY, touches[] | p5.js 2 unifies mouse+touch under the pointer model; use touches[] for multitouch. Do not add your own addEventListener('touchstart', …) |
| Drawing the camera feed | image(cam, x, y, w, h) + cam.mapKeypoint()/mapBox() | PhoneCamera integrates with p5's image(); map ML5 results with its helpers, not manual video compositing |
| Microphone level / analysis | p5.AudioIn, p5.Amplitude, p5.FFT (p5.sound) | not a raw Web Audio graph |
| Generated sound | p5.Oscillator, p5.Envelope (p5.sound) | prefer over loadSound() for portability |
| Loading images/audio/JSON/font | await loadImage()/loadSound()/loadJSON()/loadFont() in async setup() | p5.js 2: load* return Promises — no preload(). See the p5js-2x skill |
| Mapping / ranges | map(), constrain(), lerp() | p5 math helpers |
Two specific traps worth calling out:
- Motion values are p5.js built-ins, not p5-phone APIs. p5-phone only requests the permission and sets
window.sensorsEnabled. The data (rotationX, accelerationX, deviceShaken(), …) comes straight from p5.js. Do not invent p5-phone getters for them.
- There is no
bleValue() getter. Read incoming BLE data from window.bleValues[name] or from the bleReceive(name, value) callback. bleValues is an object keyed by characteristic name.
Permissions model
Every hardware family exposes the same five activation styles. Pick one:
- Tap —
enable<Feature>Tap(message) — full-screen tap overlay.
- Button —
enable<Feature>Button(buttonText, statusText?) — auto-generated button.
- Canvas —
enable<Feature>Canvas(message) — prompt drawn on the p5 canvas.
- Banner —
enable<Feature>Banner(message, position?) — animated slide-in banner (position = 'top'/'bottom').
- On (custom element) —
enable<Feature>On(selector) — bind activation to any existing HTML element by CSS selector.
Full matrix:
| Feature | Tap | Button | Canvas | Banner | On (selector) |
|---|
| Motion sensors | enableSensorTap(msg) | enableSensorButton(text) | enableSensorCanvas(msg) | enableSensorBanner(msg) | enableSensorOn(sel) |
| Microphone | enableMicTap(msg) | enableMicButton(text) | enableMicCanvas(msg) | enableMicBanner(msg) | enableMicOn(sel) |
| Sound output | enableSoundTap(msg) | enableSoundButton(text) | enableSoundCanvas(msg) | enableSoundBanner(msg) | enableSoundOn(sel) |
| Speech | enableSpeechTap(msg) | enableSpeechButton(text) | enableSpeechCanvas(msg) | enableSpeechBanner(msg) | enableSpeechOn(sel) |
| Vibration | enableVibrationTap(msg) | enableVibrationButton(text) | enableVibrationCanvas(msg) | enableVibrationBanner(msg) | enableVibrationOn(sel) |
| Torch / flashlight | enableTorchTap(msg) | enableTorchButton(text) | enableTorchCanvas(msg) | enableTorchBanner(msg) | enableTorchOn(sel) |
| NFC | enableNfcTap(msg) | enableNfcButton(text) | enableNfcCanvas(msg) | enableNfcBanner(msg) | enableNfcOn(sel) |
| GPS / geolocation | enableGeoTap(msg) | enableGeoButton(text) | enableGeoCanvas(msg) | enableGeoBanner(msg) | enableGeoOn(sel) |
| Bluetooth (BLE) | enableBleTap(opts?) | enableBleButton(opts?) | enableBleCanvas(opts?) | enableBleBanner(opts?) | enableBleOn(sel) |
| Camera | enableCameraTap(msg) | enableCameraButton(text) | enableCameraCanvas(msg) | enableCameraBanner(msg) | enableCameraOn(sel) |
| Sensors + mic | enableAllTap(msg) | enableAllButton(text) | enableAllCanvas(msg) | enableAllBanner(msg) | enableAllOn(sel) |
| Any combination | enablePermissionsTap(list, msg) | enablePermissionsButton(list, text) | enablePermissionsCanvas(list, msg) | enablePermissionsBanner(list, msg) | enablePermissionsOn(sel, list) |
Notes:
enableBle* take an options object ({ label, message, statusText, position }), unlike the other families which take positional (message, position) / (buttonText, statusText).enableGyro* is a legacy alias for enableSensor*. Prefer enableSensor* for new examples; use enableGyro* only to match older published sketches.enableAll* is shorthand for sensors + mic. For any other mix, use enablePermissions*.enableHardware* is an exact alias of enablePermissions*.
Combining features
enablePermissions* (a.k.a. enableHardware*) takes a list plus a message. The list can be an array or a space/comma string.
Canonical tokens: sensors, mic, sound, speech, vibration, torch, nfc, geo, camera.
Aliases (all normalized to the canonical tokens): sensor, motion, orientation, gyro, gyroscope, accelerometer → sensors; microphone, audioin → mic; audio, audiooutput, output → sound; voice, recognition → speech; vibrate, haptic, haptics → vibration; flashlight, flash, light → torch; tag, tags → nfc; gps, location, geolocation → geo; video, webcam → camera; all → sensors + mic.
function setup() {
createCanvas(windowWidth, windowHeight);
lockGestures();
enablePermissionsTap(['sensors', 'mic'], 'Tap to enable motion + microphone');
}
function draw() {
if (!window.sensorsEnabled || !window.micEnabled) return;
}
Status variables and callbacks
Read these window.* flags before using hardware data:
- Motion:
sensorsEnabled
- Microphone:
micEnabled
- Sound:
soundEnabled
- Speech:
speechEnabled
- Vibration:
vibrationEnabled
- Torch:
torchEnabled, torchSupported, torchActive, torchError, torchCapability
- NFC:
nfcEnabled, nfcStatus, nfcError, nfcTagAliases, lastNfcSerialNumber, lastNfcAlias, lastNfcMessage
- GPS:
geoEnabled, geoStatus, geoError, lastGeoPosition
- BLE:
bleSupported, bleConnected, bleStatus, bleError, bleDeviceName, bleValues
- Camera:
cameraEnabled
- Gestures:
gesturesLocked
Callbacks your sketch can define (p5-phone calls them if present):
userSetupComplete() — fires once immediately after permissions succeed.deviceMoved(), deviceShaken() — p5.js motion events (available after sensorsEnabled).nfcRead(message, serialNumber) — a tag was read.geoRead(position) — a new GPS position arrived. position is a plain object: { latitude, longitude, accuracy, altitude, altitudeAccuracy, heading, speed, timestamp }.onGeoError(error) — a GPS stream error after the watch started. error.code: 1=PERMISSION_DENIED, 2=POSITION_UNAVAILABLE, 3=TIMEOUT.bleReceive(name, value) — a BLE characteristic notified or was read.
function userSetupComplete() {
debug('Permissions ready');
}
Motion sensors
After window.sensorsEnabled is true, read p5.js built-ins:
- Orientation:
rotationX, rotationY, rotationZ
- Acceleration:
accelerationX, accelerationY, accelerationZ
- Rotational velocity:
rotationRateAlpha, rotationRateBeta, rotationRateGamma
- Events:
deviceMoved(), deviceShaken()
- Thresholds:
setMoveThreshold(value), setShakeThreshold(value)
- Orientation state:
deviceOrientation
iOS requires the sensor permission to be requested from a tap/click. Never auto-request motion permission on page load.
Microphone and sound
Include p5.sound and create p5.AudioIn() before enabling mic. For simple examples read levels with mic.getLevel() after window.micEnabled is true. Avoid wiring p5.Amplitude.setInput(mic) before permission — p5.sound 0.3.0 can throw in p5.js 2 previews.
let mic;
function setup() {
createCanvas(windowWidth, windowHeight);
lockGestures();
mic = new p5.AudioIn();
enableMicTap('Tap to enable microphone');
}
function draw() {
background(0);
if (!window.micEnabled) return;
const level = mic.getLevel();
circle(width / 2, height / 2, 40 + level * 600);
}
For generated audio, use enableSoundTap() (or enableSoundOn(selector)) to resume the AudioContext, then p5.Oscillator. Prefer generated sound over loadSound() unless the user provides audio assets — it is more portable in the p5 Web Editor.
Speech recognition
enableSpeech* satisfies the mobile audio/user-activation requirement and sets window.speechEnabled; it deliberately does not create a p5.AudioIn (which would conflict with the mic). After activation, create your own Web Speech API SpeechRecognition object.
Camera and ML5 (PhoneCamera)
createPhoneCamera(active = 'user', mirror = true, mode = 'fitHeight') returns a PhoneCamera. The camera is not initialized until an enableCamera* gesture (this fixes an iOS rotation bug).
active: 'user' (front) or 'environment' (rear).mirror: mirror the display (front cameras usually true).mode: 'fitHeight', 'fitWidth', 'cover', 'contain', or 'fixed'.
let cam;
let model;
function setup() {
createCanvas(405, 720);
lockGestures();
cam = createPhoneCamera('user', true, 'fitHeight');
enableCameraTap('Tap screen to enable camera');
cam.onReady(async () => {
model = await ml5.handPose({ maxHands: 1, runtime: 'mediapipe', flipped: false });
model.detectStart(cam.videoElement, gotResults);
});
}
PhoneCamera properties: ready, video (p5 element), videoElement (native <video> for ML5), width, height, active, mirror, mode, fixedWidth, fixedHeight.
Coordinate-mapping methods (video space → display space, mirror-aware):
cam.onReady(callback) — safe point to start ML5.cam.getDimensions() → { x, y, width, height, scaleX, scaleY }.cam.mapPoint(x, y) → { x, y }.cam.mapKeypoint(keypoint) / cam.mapKeypoints(keypoints).cam.mapBox(box) / cam.mapBoxes(boxes).cam.remove() — stop and clean up the camera.
Set ML5 flipped: false when available — PhoneCamera already handles mirroring and coordinate mapping, so pass raw ML5 results through the map* helpers.
For ml5@1 with p5@2.2.3, add the preload-counter polyfill before loading ml5:
<script src="https://cdn.jsdelivr.net/npm/p5@2.2.3/lib/p5.js"></script>
<script src="https://cdn.jsdelivr.net/npm/p5.js-compatibility@0.2.0/src/preload.js"></script>
<script>
p5.prototype._incrementPreload ||= function() {};
p5.prototype._decrementPreload ||= function() {};
</script>
<script src="https://unpkg.com/ml5@1/dist/ml5.min.js"></script>
For Three.js pages that use ML5 but are not p5 sketches, put p5, the compatibility shim, the preload-counter polyfill, and ml5 in the document <head> so p5 Web Editor preview injection does not run before p5 exists.
NFC
Android Chrome only, requires HTTPS. Compatible with widely available NFC Type 2 tags — NTAG213, NTAG215, NTAG216 — and any NDEF-formatted tag.
function setup() {
createCanvas(windowWidth, windowHeight);
lockGestures();
enableNfcTap('Tap to enable NFC');
}
function nfcRead(message, serialNumber) {
setNfcTagAlias(serialNumber, 'example-tag');
debug('Read NFC tag: ' + serialNumber);
}
function draw() {
background(20);
if (isNfcTag('example-tag')) {
background(0, 120, 255);
}
}
Helpers: setNfcTagAlias(serialNumber, alias), getNfcTagAlias(serialNumber?) (defaults to window.lastNfcSerialNumber), isNfcTag(aliasOrSerialNumber), stopNfc(). Track state via window.nfcStatus (idle/starting/requesting-permission/scanning/tag-read/permission-denied/unsupported/secure-context-required/error/stopped) and window.nfcError.
GPS / geolocation
Cross-platform (iOS Safari + Android Chrome), requires HTTPS. Builds on navigator.geolocation — the only well-supported API in 2026. Coarse by default (battery-friendly, ~50-100m); opt into real GPS via setGeoOptions({ enableHighAccuracy: true }) before enabling. Cold start can take 5-30s.
function setup() {
createCanvas(windowWidth, windowHeight);
lockGestures();
setGeoOptions({ enableHighAccuracy: true });
enableGeoTap('Tap to enable GPS');
}
function draw() {
background(20);
const pos = window.lastGeoPosition;
if (pos) {
text(pos.latitude.toFixed(5) + ', ' + pos.longitude.toFixed(5), width / 2, height / 2);
} else if (window.geoStatus === 'requesting-permission') {
text('Acquiring GPS…', width / 2, height / 2);
}
}
function geoRead(position) {
}
Helpers: setGeoOptions({ enableHighAccuracy?, timeout?, maximumAge? }) (call before enableGeo*), getGeoPosition() (sync last position or null), geoDistance(lat1, lon1, lat2, lon2, units) (Haversine; 'm' default, 'km', 'mi'), geoInPolygon([{lat,lon},…], {lat,lon}) (ray-casting geofence test), stopGeo(). Track state via window.geoStatus (idle/requesting-permission/active/permission-denied/unsupported/secure-context-required/error/stopped) and window.geoError. Optional error callback: onGeoError(error).
Gotchas: iOS does not track in background/locked screen; in-app browsers (Instagram/Facebook) usually fail — tell users to open in Safari; navigator.permissions.query({name:'geolocation'}) always returns 'prompt' on Safari (WebKit bug), so don't gate UI on it.
Bluetooth Low Energy (BLE)
Web Bluetooth exchanges typed values with Arduino-class peripherals. Call bleSetup() in setup() before any connect helper; connect from a user gesture via enableBle*.
Platform support:
- Chrome/Edge on Android and desktop over HTTPS (or localhost).
- iOS Safari/Chrome: not supported — use the Bluefy browser app.
- Embedded iframes need
allow="bluetooth".
function setup() {
createCanvas(windowWidth, windowHeight);
lockGestures();
bleSetup({
namePrefix: 'p5phone',
autoReconnect: true,
characteristics: [
{ name: 'temp', type: 'float', notify: true },
{ name: 'brightness', type: 'uint8', write: true }
]
});
enableBleButton({ label: 'Connect device' });
showDebug();
}
function draw() {
background(20);
if (bleConnected) {
text('temp: ' + (bleValues.temp ?? '—'), 20, 40);
}
}
function mousePressed() {
if (bleConnected) {
bleWrite('brightness', floor(map(mouseX, 0, width, 0, 255)));
}
return false;
}
function bleReceive(name, value) {
debug('BLE ' + name + ' = ' + value);
}
bleSetup(config) fields:
serviceUUID — hyphenated 128-bit UUID; defaults to the P5PhoneBLE service if omitted.namePrefix — optional device-name filter.autoReconnect — optional boolean.characteristics — required array of { name, type, read?, write?, notify?, uuid? }. Each needs at least one of read/write/notify. Omit uuid to auto-derive it from the service UUID and declaration order (must match the P5PhoneBLE Arduino side). Names must be unique.
Valid type values: bool, int8, uint8, int16, uint16, int32, uint32, float, double, string, bytes. Numeric types use little-endian byte order.
Lifecycle and I/O:
enableBle*(options) — connect from a user gesture.bleConnect() / bleDisconnect() — programmatic connect/disconnect (connect still needs a gesture).bleRead(name) — async; reads and decodes a characteristic, updates window.bleValues[name], returns the value.bleWrite(name, value, opts?) — async; opts.ack === false uses write-without-response (default is write-with-response). String writes over ~20 bytes may truncate on default-MTU peripherals.isBleSupported() — boolean.bleReceive(name, value) — your callback, fired on notify and on read.
window.bleStatus progresses through idle/connecting/connected/requesting/disconnected/error/unsupported. bleValues is not cleared on disconnect (sketches keep rendering last-known values).
Vibration
Use enableVibration* before vibrate(pattern). iOS does not support the Vibration API — write examples that still show useful feedback when window.vibrationEnabled is false.
function mousePressed() {
if (window.vibrationEnabled) {
vibrate([40, 30, 80]);
}
return false;
}
stopVibration() cancels an ongoing pattern.
Torch / flashlight
Android-Chrome-oriented, requires HTTPS, works through a rear-camera stream. Enable with enableTorch*() (or enablePermissions*(['torch'])), then control the light:
torchOn(), torchOff(), toggleTorch(), setTorch(enabled) (async), stopTorch(), isTorchSupported().- Flashlight aliases:
enableFlashlight*, flashlightOn(), flashlightOff(), toggleFlashlight(), setFlashlight(), stopFlashlight().
function setup() {
createCanvas(windowWidth, windowHeight);
lockGestures();
enablePermissionsTap(['sensors', 'torch'], 'Tap to enable shake flashlight');
}
async function deviceShaken() {
if (window.sensorsEnabled && window.torchEnabled) {
await toggleTorch();
}
}
Keep flashing pulses slow and short, avoid rapid strobing, and call torchOff() or stopTorch() when the effect ends.
lockGestures reference
lockGestures(options?)
options:
mode — 'fullscreen' (default) or 'embedded'.element — target element for embedded mode (defaults to the first <canvas>).warnBeforeLeave — show a leave-confirmation prompt (default false).trapHistory — trap back/forward navigation (default true in fullscreen, false in embedded).
Use bare lockGestures() for full-screen mobile sketches. Use lockGestures({ mode: 'embedded', element: canvas }) for a canvas embedded in a scrollable, multi-section page — it scopes gesture blocking to that canvas so the rest of the page still scrolls. unlockGestures() restores the saved handlers, listeners, and styles. window.gesturesLocked reflects the current state.
Caveat: p5 touch/mouse callbacks are snapshotted when gestures lock. If you assign window.mousePressed = ... after lockGestures(), you replace p5-phone's wrapper. Define your callbacks before locking, or reassign is fine as long as you return false from them.
Debug console
For on-device troubleshooting, call showDebug() once in setup(), then log:
debug(message), debugWarn(message), debugError(message)hideDebug(), toggleDebug()
Most useful for camera, NFC, BLE, and permission troubleshooting. Use sparingly in finished examples.
Platform support matrix
| Feature | iOS Safari | Android Chrome |
|---|
| Motion sensors | ✓ (permission tap required) | ✓ (no prompt) |
| Microphone | ✓ | ✓ |
| Sound output | ✓ | ✓ |
| Speech recognition | Web Speech API support varies | ✓ |
| Camera | ✓ | ✓ |
| Vibration | ✗ (API absent) | ✓ |
| Torch / flashlight | ✗ | ✓ |
| NFC | ✗ | ✓ (HTTPS) |
| GPS / geolocation | ✓ (HTTPS, user gesture) | ✓ (HTTPS, user gesture) |
| Bluetooth BLE | ✗ (use Bluefy app) | ✓ (HTTPS) |
All hardware requires a secure context (HTTPS or localhost).
Troubleshooting
- Permission never fires /
*Enabled stays false — the request must run inside a user gesture. Confirm you used an enable* activation UI and did not call it on load. On iOS a single gesture only grants one activation window, so combine features with one enablePermissions* call.
- ML5 throws about
_incrementPreload / preload with p5@2.2.3 — add the preload-counter polyfill shim before loading ml5 (see Camera section).
- Torch or NFC does nothing — both are Android-Chrome + HTTPS only; check
window.torchSupported / window.nfcStatus.
- GPS hangs on "Acquiring…" or times out — cold start can take 5-30s, longer indoors; move outdoors, retry, and confirm OS-level Location Services is on.
window.geoStatus tells you which state you're in.
- GPS denied even after tapping Allow — the OS-level Location Services toggle (iOS Settings → Privacy & Security → Location Services; Android Settings → Location) must also be on; in-app browsers (Instagram/Facebook) usually fail — open in Safari/Chrome.
- BLE won't connect on iPhone — Web Bluetooth is unavailable in iOS Safari/Chrome; use the Bluefy app.
- Touch callbacks never run —
touchStarted/Moved/Ended are no-ops in p5.js 2; switch to mousePressed/mouseDragged/mouseReleased.
- Mic example throws in preview — don't call
p5.Amplitude.setInput(mic) before window.micEnabled; read mic.getLevel() after permission.
Answering questions
- Explain the browser-permission reason, especially iOS transient user activation.
- Distinguish sensors, mic, sound-only, speech, camera, vibration, torch, NFC, and GPS permissions.
- Mention HTTPS requirements for mobile hardware.
- Mention p5.js 2 event changes when touch callbacks are involved.
- Flag browser/device limits clearly: torch and NFC are Android-Chrome-oriented; vibration is unsupported on iOS; BLE needs Bluefy on iOS; speech recognition depends on Web Speech API support.
- Point to the bundled examples under
examples/ when useful — feature folders include movement/, microphone/, sound/, touch/, vibration/, camera/, torch/, nfc/, geo/, ble/, and combined/, plus ml5/, UIStyles/, and UXcompare/.
- When migrating examples to the p5 Web Editor, follow the web-editor batch-sync workflow in
docs/web-editor/ and record links in webeditorLinks.md.
Example quality checklist
Before finishing generated code, confirm:
lockGestures() is called in setup().- The permission request happens from a user-activation path (tap, button, banner, canvas, or custom element).
- Hardware data is read only after the matching
window.*Enabled flag is true.
- The HTML includes the needed dependencies and no unused heavy libraries.
- p5.js 2-compatible
mouse* callbacks are used (not p5 1.x touch callbacks).
- Text and canvas output fit mobile screens.
- Asset-dependent examples either include the assets or clearly document that the user must upload them.
- ML5 camera examples include the p5 2 compatibility shim and use
PhoneCamera mapping helpers.
