Overview

A Nexmo application contains the security and configuration information you need to connect to Nexmo endpoints and use the Nexmo APIs.

Each Nexmo application created can support multiple capabilities - for example you can create an Application that supports using the Voice, Messages and RTC APIs.

NOTE: This section of the docs describes Applications V2 functionality.

Structure

Each application has the following:

Name	Description
`id`	Used to identify each application and used in conjunction with `private_key` to generate JWTs.
`name`	The application name.
`capabilities`	Describes the types of functionality this application will support. The capabilities `voice`, `messages`, `rtc`, `vbc`. Any number of these capabilities can be supported in one application. You also set `webhooks` for each capability specified. Nexmo sends and retrieves information via the webhook endpoints.
`keys`	Contains `private_key` and `public_key`. You use the private key to generate the JWTs used to authenticate your calls to the Nexmo APIs. The public key is used by Nexmo to authenticate the JWT in your requests to Nexmo API.

Application capabilities

A Nexmo application can use various APIs, including Voice, Messages and Dispatch, Conversation, and Client SDK.

When creating an application you can specify the capabilities you want your application to support. For each capability you can set webhooks depending on what capabilities you want, for example for an application with an rtc capability you could specify an event URL to receive RTC events. If your application also needed to use voice capabilities you could also potentially set an Answer URL to receive a call answered webhook, and another Event URL to receive voice call related events.

A summary of capabilities is given in the following table:

Capability	Description
`voice`	Used to support Voice capabilities.
`messages`	Used to support Messages and Dispatch API capabilities.
`rtc`	Used to support WebRTC capabilities. Typically for use with Client SDK.
`vbc`	Used to determine pricing, but currently has no other capabilities.

Webhooks

The webhook URLs you provide when creating an application depend on the application capabilities required. The following table summarizes the webhooks:

Capability	API used	Webhooks available
`voice`	Voice	`answer_url`, `event_url`
`messages`	Messages and Dispatch	`inbound_url`, `status_url`
`rtc`	Client SDK	`event_url`
`vbc`	VBC	None

Webhook types

The following table describes webhooks available per capability:

Capability	Webhook	API	Example	Description
`voice`	`answer_url`	Voice	https://example.com/webhooks/answer	The URL that Nexmo make a request to when a call is placed/received. Must return an NCCO.
`voice`	`event_url`	Voice	https://example.com/webhooks/event	Nexmo will send call events (e.g. ringing, answered) to this URL.
`messages`	`inbound_url`	Messages, Dispatch	https://example.com/webhooks/inbound	Nexmo will forward inbound messages to this URL.
`messages`	`status_url`	Messages, Dispatch	https://example.com/webhooks/status	Nexmo will send message status updates (for example, `delivered`, `seen`) to this URL.
`rtc`	`event_url`	Client SDK, Conversation	https://example.com/webhooks/rtcevent	Nexmo will send RTC events to this URL.
`vbc`	None	Voice endpoint	None	Not used

Creating applications

There are four main ways to create an application:

In the Nexmo Dashboard you can create an application with a single capability. You can then add capabilities and update the details of an application created in the Dashboard using the v2 API. If an application has multiple capabilities it will appear in all relevant sections of the Dashboard. For example, an application with both Voice and Messages capabilities will appear in both the Voice and Messages sections of the Dashboard.
Using the Nexmo CLI (this is currently restricted to v1 Applications with a single fixed capability).
Using the Applications API.
Using one of the Nexmo client libraries (this is currently restricted to v1 Applications with a single fixed capability).