URL Handler
Home Assistant supports opening from other apps via URL.
Query parameters are passed as a dictionary in the call.
If multiple servers are connected to an iOS or Mac app, you will be prompted to select a server when handling a navigate link, call_service, or fire_event links will be handled using the first server in the list.
BETA
If multiple servers are connected to an Android app, navigate links will be handled using the most recently used server in the list.
Navigate
This allows you to update the frontend page location via a deeplink.
For example: if you had a dashboard at /lovelace/webcams you can use homeassistant://navigate/lovelace/webcams to launch the app there.
Call service
Example: homeassistant://call_service/device_tracker.see?entity_id=device_tracker.entity
Fire event
You can create an event trigger and fire the event.
Example: homeassistant://fire_event/custom_event?entity_id=MY_CUSTOM_EVENT
Send one shot location
Example: homeassistant://send_location/