I am currently using GCM to notify 500 000 unique android users from my third party server. Everything is going fine for months. It appears that some users are uninstalling my app and gcm service doesn't tell me that the current user is not anymore using the app whith ["NotRegistered" error code](https://developer.android.com/google/gcm/http.html#response). 

For example:

1. I install the app, and send the gcm\_id to my third party server
2. I uninstall the app
3. I try to send a event to the app through gcm from my third party server :

> 
> 
> ```
> {
>   "collapse_key" : "collapse_key_1",
>   "data" : {
>       "EVENT" : "{\"myKey\":\"myValue\"}"
>   },
>   "time_to_live" : 30,
>   "registration_ids" : ["APA91bFvdRWZimIXJMmIXvss1D-jRPQEg-1bTJ7w9LwOPNzMkSdI0UojnIjxkY8FMamrTUyBecZ2a44u1Fy1qKmcnSQLpxi2Nmw5hBUJdECXmh1jOXMW5dcXFF0OEdVLBvTLPro9ToxqrWsmq5GhtKP0BV1-HQOAQ"]
> }
> 
> ```
> 
> 

and get the response:

```
{
    "multicast_id" : 5965047050545487565,
    "success" : 1,
    "failure" : 0,
    "canonical_ids" : 0,
    "results" : [{
            "message_id" : "0:1428954436986778%d127aaafb324bdbf"
        }
    ]
}

```

I should receive a failure message (with NotRegistered code) from gcm because I uninstalled the app.