What login system would you prefer? We're currently doing Google Authentication because it's the best way for us to uphold Google privacy best practices, but can chat with folks about what other types of authentication might be possible.

Why does it need a user account at all? You say it's to uphold privacy best practices, but I don't know what data it's collecting from my phone. I would hope none. But if no data is collected, I don't see why any authentication is required.

We need a user account to store your progress: what puzzles you've completed, what code you've entered in order to save progress if you didn't complete the puzzle yet, coding streaks, etc. We're not collecting information about your device.

It's been easiest for us to do this user account creation using out-of-the-box Google Authentication, so that's why we went down this route. Hope that makes sense!

So to sum up : you’re not collecting information, you just want the user to be able to retrieve what he has already done.

First, you should ask for an account creation only when the user have already started. As I said, I didn’t even see if it was interesting at all, because of the login wall.

Second, if there are no sensitive information collected, there is no need of using a mountain to hit the nail. A pseudo will be enough. No email needed. Not sure if it even need a password... You store the pseudo locally and you are done.

(I agree I’m a little bit oversimplifying, but you see the point)

A username and a password. All this third party login nonsense needs to go. I just spent the better part of last week actively removing myself from all things google and I’ll be damned if I am going to throw that away over a coding app.