When your user opens your app for the first time, it'll be registered with a unique ID on Pushbots, you can always use that id to identify the user and send push notificaitons.

To get the Pushbots ID you can use the following method: 

For iOS

 [Pushbots getDevice:^(NSDictionary *device, NSError *error) {
    if(device != nil){
        NSLog(@"id: %s", [device valueForKey:@"_id"]);


Pushbots.getDevice { (device, error) in
    if(device != nil){
        let device_id = device?["_id"]
        print(device_id! as! NSString)

For Android 

//Register custom fields after user registered on PushBots
Pushbots.sharedInstance().idsCallback(new Pushbots.idHandler() {
    public void userIDs(String userId, String registrationId) {
        if (registrationId != null && userId != null){
            Log.d("PB3", "PushBots ID:" + userId );

For Phonegap/Cordova

//Get user registrationId/token and userId on PushBots, with evey launch of the app even launching with notification
window.plugins.PushbotsPlugin.on("user:ids", function(data){
console.log("ID" + data.id);

For web:

PB.events.push(["onRegisteredOnPushBots", function(data){
console.log("ID:", data.userId);

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