Warning: Mostly mobile-only. Control Device Permissions, Control Push Notifications, Control Biometrics and Mobile Utils appear in the action picker only in mobile apps. If one of them runs in a web app anyway (for example, on a page copied from a mobile app), Control Device Permissions, Control Push Notifications and Mobile Utils do nothing, and Control Biometrics fails, so its On Failure actions run. Control User Location (Update Geolocation) and Send MQTT Event work in both web and mobile apps.

Overview

These actions use the device: permissions, push registration, location, biometric sign-in, image preloading and MQTT messages. Each section below lists the action's fields and what it writes.

Actions at a Glance

controlDevicePermissions — Control Device Permissions

Checks or requests an OS-level permission on a native mobile device. The result is written to device context under deviceContext.permissions.<type>.allowed — read it via a binding, not a return value. The entry exists only after the action has run for that permission.

Parameters

Output — Device Context Keys

Tip: Pattern: Request a permission first, then bind the dependent feature's visibility to the result in device context. Bindings re-evaluate as soon as the result is written.

Examples

Request camera permission before scanning

{ "actionType": "controlDevicePermissions", "payload": { "operation": "request", "permissionType": "CAMERA" } } // Then bind the scanner's visibility: // visibility conditions → {{ deviceContext.permissions.camera.allowed }} EQUAL true

Check location permission silently

{ "actionType": "controlDevicePermissions", "payload": { "operation": "check", "permissionType": "LOCATION" } }

controlPushNotifications — Control Push Notifications

Registers the current native device for push notifications: requests OS notification permission, obtains the device's push token, and saves it to the backend so the device can receive server-sent pushes.

Parameters

Warning: Silent no-op conditions: The action does nothing, and shows no message, when:

• It runs in a web app.

• Push notifications are not enabled for the app. There is no builder setting for this; ask the UnifyApps team to turn push on for your app.

• The app is a public app (push targets signed-in users).

• The device's push token can't be fetched.

The only case that shows anything is a permanently blocked permission: the user sees an alert offering Go to Settings.

Register for push after the user opts in

{ "actionType": "controlPushNotifications", "payload": { "operation": "registerPushNotifications" } }

controlUserLocation — Update Geolocation

Reads the device's current GPS coordinates once and writes them to device context under deviceContext.location. Works on both web (browser location API) and native mobile. Requires Enable Location Tracking to be on in Settings → Advanced Settings → Location Tracking.

Parameters

This action takes no configurable inputs. In the builder, add Control User Location and set User Action to Update Geolocation. It is saved as action type controlUserLocation with "userControlAction": "updateGeolocation". For continuous background tracking with the same action, see Track Live Location.

Output — Device Context

Warning: Fails when location tracking is disabled. The action checks the interface's location tracking setting first. If disabled, it fails with "Location tracking is not enabled" without reading any position. Also fails if permission is denied — but still writes the denied status to device context before failing.

Capture location for a nearby search

// Action: Control User Location → Update Geolocation // (no payload fields needed) // Then bind to the coordinates: {{ deviceContext.location.coordinates.latitude }}, {{ deviceContext.location.coordinates.longitude }}

manageBiometrics — Control Biometrics

Enrolls, revokes, or verifies biometric (fingerprint/face) login for the current user on a native mobile device. In a web browser it fails, so its On Failure actions run.

Parameters

Result and Failure

• The action returns no value to the page. Use its On Success and On Failure actions to react to the result.

• verify: On Success runs only after the user passes the biometric prompt and the signed challenge is accepted. If biometrics aren't available, the user cancels or fails the prompt, or the check is rejected, the action fails and On Failure runs. Gate the next step of a biometric login on On Success.

• enroll and revoke also fail, and run On Failure, when biometrics aren't available on the device.

Examples

Enable Face ID / fingerprint login

{ "actionType": "manageBiometrics", "payload": { "method": "enroll" } }

Verify biometrics on login

{ "actionType": "manageBiometrics", "payload": { "method": "verify" } }

mobileUtils — Mobile Utils (Preload Media)

Preloads a list of image URLs into the device's cache so the next screens render instantly without visible loading delays. Only available in mobile apps.

Parameters

Note: Use case: Fire this on onPageLoad of a landing or list screen, passing the image URLs of the next screen's hero images. Navigation to that screen will then render images immediately.

Preload hero images for the next screen

{ "actionType": "mobileUtils", "payload": { "operation": "preloadMedia", "urls": "{{ ds_products['data'].map(p => p.imageUrl) }}" } }

sendMQTTEvent — Send MQTT Event

Publishes a message to one of your app's configured MQTT topics. Choose the topic in MQTT Topic and fill in Event Message using the fields of the topic's message schema. The platform manages the MQTT connection, so you don't set up a broker yourself. For topic setup, message schemas and receiving messages, see Realtime & MQTT.

Common Patterns

Permission Gate Pattern

The canonical pattern for permission-gated features:

1. Request the permission: Wire controlDevicePermissions with operation: "request" to a button click event.

2. Read the result from device context: Bind the feature's visibility to {{ deviceContext.permissions.camera.allowed }} (or the relevant key). Bindings re-evaluate automatically once the result is written.

3. Handle the denied case: Add a visibility condition for the "permission denied" message bound to {{ deviceContext.permissions.camera.allowed }} EQUAL false.