# Android

Once you've started receiving data from a [device](https://app.gitbook.com/s/eJJpVMsUARUJq9lYmL6t/streaming-api/core-concepts#device) into your app, you can start sending this data to Terra's websocket server (the [broker](https://app.gitbook.com/s/eJJpVMsUARUJq9lYmL6t/streaming-api/core-concepts#broker)).

This will later allow you to receive it on your backend, and process it as per your requirements.

{% hint style="info" %}

#### Prerequisite

Before following the steps below, make sure you've followed the guide to [stream data from a wearable device to your app](https://docs.tryterra.co/streaming-api/connect-wearable-to-sdk/android)
{% endhint %}

## Setting up a connection

You'll have previously set up a stream between a wearable [device](https://app.gitbook.com/s/eJJpVMsUARUJq9lYmL6t/streaming-api/core-concepts#device) and your app [using the startRealtime function](https://docs.tryterra.co/connect-wearable-to-sdk/android#start-real-time-streaming). In order to send this data to the [broker](https://app.gitbook.com/s/eJJpVMsUARUJq9lYmL6t/streaming-api/core-concepts#broker), use the `startRealtime` overload that accepts a `token`:

```kotlin
import co.tryterra.terrartandroid.TerraRT
import co.tryterra.terrartandroid.enums.Connections
import co.tryterra.terrartandroid.enums.DataTypes
import co.tryterra.terrartandroid.models.Update

// Assumes terraRT is already initialized and a device is connected
// (see the "Connect Wearable to SDK" guide)

val token = "yourStreamingToken"  // Generated from your backend (see below)
val dataTypes = setOf(DataTypes.HEART_RATE, DataTypes.STEPS)

// Stream to BOTH your app AND Terra's websocket server
terraRT.startRealtime(
    type = Connections.BLE,
    dataTypes = dataTypes,
    token = token,
    updateHandler = { update ->
        println("${update.type}: ${update.`val`} at ${update.ts}")
    },
    connectionCallback = { connected ->
        println("Websocket connected: $connected")
    }
)
```

Simply passing in a token from the following endpoint will allow you to stream the same data you were reading previously within your app, and have it sent to the broker.

{% hint style="info" %}
Make sure to pass in the correct user ID in the `id` query parameter in the call below. You may retrieve that user ID using the [`getUserId`](https://app.gitbook.com/s/eJJpVMsUARUJq9lYmL6t/streaming-api/reference/android-kotlin#getuserid) function in the SDK.
{% endhint %}

{% openapi src="<https://raw.githubusercontent.com/tryterra/openapi/refs/heads/master/rt.yml>" path="/auth/user" method="post" %}
<https://raw.githubusercontent.com/tryterra/openapi/refs/heads/master/rt.yml>
{% endopenapi %}