All device APIs in Mob follow a consistent pattern: call the function from a callback (returning the socket unchanged), then handle the result in handle_info/2. APIs never block the screen process.

Permissions

Some capabilities require an OS permission before they can be used. Request permissions via Mob.Permissions.request/2. The result arrives asynchronously:

def mount(_params, _session, socket) do
  socket = Mob.Permissions.request(socket, :camera)
  {:ok, socket}
end

def handle_info({:permission, :camera, :granted}, socket) do
  {:noreply, Mob.Socket.assign(socket, :camera_ready, true)}
end

def handle_info({:permission, :camera, :denied}, socket) do
  {:noreply, Mob.Socket.assign(socket, :camera_ready, false)}
end

Capabilities that require permission: :camera, :microphone, :photo_library, :location, :notifications

No permission needed: haptics, clipboard, share sheet, file picker.

Haptic feedback

Mob.Haptic.trigger/2 fires synchronously (no handle_info needed) and returns the socket:

def handle_event("tap", %{"tag" => "purchase"}, socket) do
  socket = Mob.Haptic.trigger(socket, :success)
  {:noreply, socket}
end

Feedback types: :light, :medium, :heavy, :success, :error, :warning

iOS uses UIImpactFeedbackGenerator / UINotificationFeedbackGenerator. Android uses View.performHapticFeedback.

Clipboard

# Write to clipboard
def handle_event("tap", %{"tag" => "copy"}, socket) do
  socket = Mob.Clipboard.write(socket, socket.assigns.code)
  {:noreply, socket}
end

# Read from clipboard — result arrives in handle_info
def handle_event("tap", %{"tag" => "paste"}, socket) do
  socket = Mob.Clipboard.read(socket)
  {:noreply, socket}
end

def handle_info({:clipboard, :read, text}, socket) do
  {:noreply, Mob.Socket.assign(socket, :pasted_text, text)}
end

Share sheet

Opens the platform's native share sheet (iOS: UIActivityViewController, Android: ACTION_SEND):

def handle_event("tap", %{"tag" => "share"}, socket) do
  socket = Mob.Share.sheet(socket, text: "Check out this app!", url: "https://example.com")
  {:noreply, socket}
end

Options: :text, :url, :title

Camera

Requires :camera permission (and :microphone for video).

# Capture a photo
socket = Mob.Camera.capture_photo(socket)
socket = Mob.Camera.capture_photo(socket, quality: :medium)

# Record a video
socket = Mob.Camera.capture_video(socket)
socket = Mob.Camera.capture_video(socket, max_duration: 30)

# Results:
def handle_info({:camera, :photo, %{path: path, width: w, height: h}}, socket) do
  {:noreply, Mob.Socket.assign(socket, :photo_path, path)}
end

def handle_info({:camera, :video, %{path: path, duration: seconds}}, socket) do
  {:noreply, Mob.Socket.assign(socket, :video_path, path)}
end

def handle_info({:camera, :cancelled}, socket) do
  {:noreply, socket}
end

path is a local temp file. Copy it to a permanent location before the next capture.

Photos

Browse and pick from the photo library. Requires :photo_library permission.

socket = Mob.Photos.pick(socket)
socket = Mob.Photos.pick(socket, max: 5)  # pick up to 5

def handle_info({:photos, :picked, photos}, socket) do
  # photos is a list of %{path: path, width: w, height: h} maps
  {:noreply, Mob.Socket.assign(socket, :photos, photos)}
end

def handle_info({:photos, :cancelled}, socket) do
  {:noreply, socket}
end

Files

Open the system file picker:

socket = Mob.Files.pick(socket)
socket = Mob.Files.pick(socket, types: ["public.pdf", "public.text"])  # iOS UTI strings
socket = Mob.Files.pick(socket, types: ["application/pdf", "text/plain"])  # Android MIME types

def handle_info({:files, :picked, files}, socket) do
  # files is a list of %{path: path, name: name, size: bytes} maps
  {:noreply, Mob.Socket.assign(socket, :files, files)}
end

Platform note: types uses iOS UTI strings on iOS ("public.pdf") and MIME type strings on Android ("application/pdf"). To support both platforms with the same call, pass both forms — the platform ignores strings it doesn't recognise. See Platform-specific props for a cleaner pattern.

## Audio recording

Requires `:microphone` permission.

socket = Mob.Audio.record(socket) socket = Mob.Audio.record(socket, format: :aac, max_duration: 120) socket = Mob.Audio.stop_recording(socket)

def handle_info({:audio, :recorded, %{path: path, duration: seconds}}, socket) do

end

## Location

Requires `:location` permission.

Single fix

socket = Mob.Location.get_once(socket)

Continuous updates

socket = Mob.Location.start(socket) socket = Mob.Location.start(socket, accuracy: :high) # :high | :balanced | :low socket = Mob.Location.stop(socket)

def handle_info({:location, %{lat: lat, lon: lon, accuracy: acc, altitude: alt}}, socket) do {:noreply, Mob.Socket.assign(socket, :location, %{lat: lat, lon: lon})} end

def handle_info({:location, :error, reason}, socket) do

end

iOS uses `CLLocationManager`. Android uses `FusedLocationProviderClient`.

## Motion (accelerometer / gyroscope)

socket = Mob.Motion.start(socket) socket = Mob.Motion.start(socket, interval_ms: 100) socket = Mob.Motion.stop(socket)

def handle_info({:motion, %{ax: ax, ay: ay, az: az, gx: gx, gy: gy, gz: gz}}, socket) do {:noreply, Mob.Socket.assign(socket, :motion, %{ax: ax, ay: ay, az: az})} end

## Biometric authentication

socket = Mob.Biometric.authenticate(socket, reason: "Confirm your identity")

def handle_info({:biometric, :success}, socket) do

end

def handle_info({:biometric, :failure, reason}, socket) do

end

iOS uses Face ID / Touch ID. Android uses `BiometricPrompt`.

## QR / barcode scanner

socket = Mob.Scanner.scan(socket)

def handle_info({:scan, :result, %{type: type, value: value}}, socket) do # type: :qr | :ean | :upc | etc.

end

def handle_info({:scan, :cancelled}, socket) do

end

## Notifications

See also [Mob.Notify](Mob.Notify.html) for the full API.

Requires `:notifications` permission.

### Local notifications

Schedule

Mob.Notify.schedule(socket, id: "reminder_1", title: "Time to check in", body: "Open the app to see today's updates", at: ~U[2026-04-16 09:00:00Z], # or delay_seconds: 60 data: %{screen: "reminders"} )

Cancel

Mob.Notify.cancel(socket, "reminder_1")

Receive in handle_info (all app states: foreground, background, relaunched):

def handle_info({:notification, %{id: id, data: data, source: :local}}, socket) do

end

### Push notifications

Register for push tokens and forward them to your server. A server-side push library (`mob_push`) is planned but not yet published — for now, use a standard APNs/FCM client library with the tokens you receive.

After :notifications permission is granted:

Mob.Notify.register_push(socket)

Receive the device token:

def handle_info({:push_token, :ios, token}, socket) do MyApp.Server.register_token(:ios, token)

end

def handle_info({:push_token, :android, token}, socket) do MyApp.Server.register_token(:android, token)

end

Receive push notifications:

def handle_info({:notification, %{title: t, body: b, data: d, source: :push}}, socket) do

end