set-up-sns.js

sns.createPlatformEndpointAsync({
    PlatformApplicationArn: applicationArn,
    Token: deviceId,
});

/* send the notification (not needed) */
sns.publishAsync({
    MessageStructure: "json",
    Message: JSON.stringify({
    APNS: JSON.stringify({
        aps: messageJson
    }),
    TargetArn: deviceArn,
});

/* subscribe device to topic */
sns.subscribeAsync({
    Protocol: 'application',
    TopicArn,
    // Acquired from `createPlatformEndpoint`
    Endpoint, 
});