I'm not sure if this is a problem with the app. I think it's automatically redirecting because you're already logged in using the first account. And github on their website too does not support multiple logins so you would not be able to choose an account. I think if you logout of your account from the browser and try logging in to the different one using the app it should work. (Perhaps we should handle duplicate account creation on the app). Or another way is for us to implement an in app browser that will not remember the login.

Edit: I was wrong. Fixing it now

Thank you!