I want to create some mail apps , and I want as first step the user login with his Google account (just in first time) and then to get all messages / sent messages after the authentication
I see many issues about this question like:
But I did not find any clear question as to what is the best way to go.
So I try to understand what is the best option for me? I try 2 different options:
Google Sign-in button on Android - I success to create the sign-in but I couldn't add Gmail scopes to GoogleSignInOptions object because it's not part of the the built scopes , any question that I see get is just the basic information about user but it's not my purpose .
Android quick start for Gmail API - Also here I run this but I don't know why there is the first part of getting permissions for contacts?? If somehow I can do this without this step it will be great, and maybe it's the best option (?)
My third option is that I don't find it's to use Gmail REST API with refresh and access token because I know it and already use it in different issues but I think this is not the case here.
So in summary - for my purpose, what way I need to choose ?