Authenticate from a Non-Trusted Device

There are 2 steps in authenticating a Non-Trusted Device

  1. Make a request from the Non-Trusted Device and wait for approval

  2. Approve the request from a Trusted Device.

Step 1: Making an Authentication Request

Same as how it works with Authenticating from a Trusted Device, to authenticate a device, call the TrustedDeviceHelper.requestAuth function. This will automatically detect whether the current device is a Trusted Device or not.

Cotter.signInWithDevice(this, userEmail, this, Dashboard.class, new Callback() {
    public void onSuccess(JSONObject result) {
        Toast.makeText(getApplicationContext(), result.toString(), Toast.LENGTH_SHORT).show();
        Log.e("Success authenticating user", result.toString() );

    public void onError(String error) {
        Toast.makeText(getApplicationContext(), error, Toast.LENGTH_SHORT).show();

Callback Class

The Callback.class should be filled with the Activity to go to when the request is approved. For example, if this is a login request, then the Callback Activity can be your Dashboard class.

When an Authentication Event is requested TRUSTED_DEVICE, there are 2 possible cases:

Case 1: The current device is a Trusted Device

You will be automatically approved if the request is coming from a Trusted Device. This is covered in Authenticate from a Trusted Device.

Case 2: The current device is NOT a Trusted Device

If the current device is not a Trusted Device, then it will create a pending event. This pending event will need to be approved by a Trusted Device.

The SDK will automatically show a prompt for the user to approve the event from a Trusted Device. The user then need to approve this request from their Trusted Device:

Step 2: How to approve a pending request from a Trusted Device

To check if there's a pending event for this user, you can call the getNewEvent method from a Trusted Device.

TrustedDeviceHelper.getNewEvent(getApplicationContext(), this);

In the future, your app that is installed in a Trusted Device will receive a notification and this method is invoked when the notification is opened.

For now, you should tell your user to press a button and invoke this method when they try to login from a non-trusted device.

The SDK will open a prompt in the Trusted Device asking if the user want to approve or reject the authentication request.

In the prompt in the user's Non-Trusted Device (right picture), you can Customize the Prompt to ask them to press a specific button in the Trusted Device to invoke the prompt on the left.

Receiving the result and check if the request was approved

In the non-trusted device where the user is trying to log in, you'll receive the result in the callback class that your specified.

Case 1: The request is approved

When the request is approved, the SDK will automatically redirect to your Callback Class. In the callback class, you should handle the response from Cotter

Handle the response in your callback class

protected void onCreate(Bundle savedInstanceState) {

    // Handle the response
    TrustedDeviceResponse trustDevResp = TrustedDeviceHelper.handleResponse(getIntent());
    if (trustDevResp != null) {
        Log.i("TrustedDeviceResponse: ", Integer.toString(trustDevResp.event.ID));

You'll receive a response in the form of a TrustedDeviceResponse object.

public class TrustedDeviceResponse {
    public String response; // The response in the form of a string
    public Event event; // The same response, but parsed in to an Event object
    public boolean approved; // Whether or not the event was approved
    public String error; // If there's any error, this will contain the error, otherwise null

When this authentication request is approved, you'll receive an access token in the String Response. Send this access token to your backend to validate it:

Verifying JWT Tokens

Case 2: The request is rejected

If the request is not approved for 1 minute, the prompt in the Non-Trusted Device will show an error message. The prompt will not show an error immediately when the Trusted Device denied the request, i.e. there is no difference between rejection and no response from the Trusted Device.

In this case, the onError function that you passed in earlier will be called with an error message of Event is not approved.

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