How to make authorization through the VK API in the browser and mobile applications?

Question

WordPress

I want to implement registration on the site using authorization through VKontakte, but I got confused in choosing the authorization method: the fact is that I want to implement the possibility of both authorization through the site and through mobile applications. Please tell me which method to choose and which field can uniquely identify the user (some methods return user_id, others only token, etc.).

Answer 1

wordpress.stackexchange.com/questions/120055/wooco...
Solution.