The Application Object

An Application is a named container for the webhook URLs that control your call flow. You attach a phone number or a SIP endpoint to an application so that calls fire its configured webhooks. See Application vs Endpoint below to choose the right object.

Attributes

Field	Type	Description
`app_id`	string	Unique identifier for the application. Use it in all per-application API paths.
`app_name`	string	Name of the application.
`answer_url`	string	URL Vobiz fetches when a call executes this application. Must return valid VobizXML to control the call flow.
`answer_method`	string	HTTP method for `answer_url`. One of `GET` or `POST`. Default `POST`.
`hangup_url`	string	URL notified when the call ends. Useful for analytics and cleanup. If unset at create time, defaults to `answer_url`.
`hangup_method`	string	HTTP method for `hangup_url`. One of `GET` or `POST`. Default `POST`.
`fallback_answer_url`	string (nullable)	Backup URL invoked only when `answer_url` is unreachable, times out, or returns invalid VobizXML. Must itself return valid VobizXML. `null` when unset.
`fallback_method`	string	HTTP method for `fallback_answer_url`. One of `GET` or `POST`. Default `POST`.
`message_url`	string (nullable)	URL notified when an inbound message is received. Vobiz expects an HTTP 200 response. `null` when unset.
`message_method`	string	HTTP method for `message_url`. One of `GET` or `POST`. Default `POST`.
`default_number_app`	boolean	If `true`, newly created numbers without an `app_id` are auto-routed to this application. Default `false`. Does not retroactively re-route existing numbers.
`default_endpoint_app`	boolean	If `true`, newly created endpoints without an `application` are auto-routed to this application. Default `false`. Does not retroactively re-route existing endpoints.
`sub_account`	string (nullable)	Sub-account `auth_id`. `null` for the main account. Cannot be changed after creation.
`resource_uri`	string	API resource URI for this application.
`application_type`	string	Type of application. Typically `XML` (also seen as `voice`).
`default_app`	boolean	Whether this is the account-level default application. Default `false`.
`enabled`	boolean	Whether the application is enabled. Default `true`.
`log_incoming_message`	boolean	Whether incoming messages to numbers on this application are logged. Default `true`.
`public_uri`	boolean	Whether the application’s `sip_uri` is reachable by external SIP systems. Default `false`. See Public SIP URI.
`sip_transfer_method`	string	HTTP method for SIP transfer callbacks. One of `GET` or `POST`.
`sip_transfer_url`	string (nullable)	URL notified during a SIP transfer. `null` when unset.
`sip_uri`	string	SIP URI associated with the application, e.g. `sip:<app_id>@sip.vobiz.ai`.
`created_at`	string (ISO 8601)	Creation timestamp (UTC).
`updated_at`	string (ISO 8601)	Last update timestamp (UTC).

api_id is a request-correlation ID returned alongside the object on single-object responses (Create, Retrieve, Update). It is not a persistent attribute of the application.

Example Application Object

JSON

{
  "answer_method": "POST",
  "answer_url": "https://example.com/answer",
  "api_id": "aabbccdd-1234-5678-90ab-cdef12345678",
  "app_id": "12345678901234567",
  "app_name": "My Voice App",
  "application_type": "XML",
  "created_at": "2026-04-02 12:11:19.740666+00:00",
  "default_app": false,
  "default_endpoint_app": false,
  "enabled": true,
  "fallback_answer_url": null,
  "fallback_method": "POST",
  "hangup_method": "POST",
  "hangup_url": "https://example.com/hangup",
  "log_incoming_message": true,
  "message_method": "POST",
  "message_url": null,
  "public_uri": false,
  "resource_uri": "/v1/Account/MA_XXXXXXXX/Application/12345678901234567/",
  "sip_transfer_method": "POST",
  "sip_transfer_url": null,
  "sip_uri": "sip:12345678901234567@app.vobiz.ai",
  "sub_account": null,
  "updated_at": "2026-04-02 12:11:19.740666+00:00"
}

Application vs Endpoint

You want to…	Use
Route inbound calls on a phone number (DID) to your webhooks	An Application, then attach the number to it.
Let a device or person (browser, softphone, desk phone, AI agent) place and receive calls	An Endpoint, with an Application attached for its call logic.
Both - a number rings, then routes to a device	A number attached to an Application whose VobizXML `Dial`s the endpoint’s `sip_uri`.

Public SIP URI

Every application has a sip_uri such as sip:<app_id>@sip.vobiz.ai. By default public_uri is false, meaning the URI is not exposed to external SIP systems. Set public_uri: true only when a third-party SIP system - for example another PBX or carrier - needs to route calls directly into this application’s sip_uri. For ordinary inbound flows driven by a Vobiz phone number, leave public_uri as false.

​Attributes

​Example Application Object

​Application vs Endpoint

​Public SIP URI

Attributes

Example Application Object

Application vs Endpoint

Public SIP URI