@MiaWinter Apple iCloud?
@MiaWinter it fulfils the requirements and they're pushing their SSO on anyone who has an app in their store (and offers other services' SSO)
@MiaWinter I didn't know you talk in spirit, not in words and all SSO services that have significant adoption are large tech companies
@noiob I think you didn't get the spirit here of me specifying "not MS or Google"