As a result of the login, the Android app receives userToken, which uniquely identifies the user and his/her session.

On the Android app, a user logs in to Backendless with their user name and password.

The message will be sent by the Android app later (step 5).

Then the web app connects to the messaging channel and waits for a message.

The web app downloads the generated QR code and displays it on the web page.

The service returns the QR code and the name of the channel channelName to the web app. In this case, that value is the name of a Backendless messaging channel.

A custom API service generates a QR code with an encoded unique value.

The initial page of your web application makes a request to the server to generate a QR code.

The overall process consists of the following steps:

and you have basic programming experience with Android.

you know how to work with the Backendless CodeRunner utility and Backendless SDK for Java ,.

you are already familiar with the How to generate a QR code with Backendless API Service article,.

you already have a Backendless account (if not, sign up free here),.

For example, to login into a web session with WhatsАpp, you must log in on your phone and then scan a QR code in the web interface. There are several examples of popular apps which use this approach.

Suppose that a user is already authenticated in your application (in our example, it would be an android app) and the user wants to use their actual session to perform an automatic authentication in another application (in my case it’s a web app). What does “mobile-to-web cross login with a QR code” mean? It is one of the approaches for two-factor authentication.

Outlook qr code sign in mobile