Google OAuth 2.0 and Captive portal with Embedded browser

Question

Both Android and IOS devices have a mechanism to detect captive portal on Guest Wifi networks. Whenever a captive portal is detected, these devices start an embedded browser

Answer 1

I'm not cool enough to comment apparently, so I'll just reply that despite @nvagr stating that google will not be broken in the CNA, it is. You cannot log in using Google oAuth on an iOS device. You'll get a 403: disallowed_useragent because it uses the CNA.