I am close to publishing an iOS app built in Flutter. I've read that apps need to support IPv6 networks but what is not clear is that whether or not our API (restful web-service) needs to be IPv6 enabled. I am confident the app will work over IPv6 network but not with our web-service which is not IPv6 enabled at the moment. Enabling IPv6 on the web-service is currently not an option for us.
So my question really is; would my app get rejected because our restful web-service is not IPv6 enabled, but the app will work if we decide to switch the web-service to IPv6 only?
I can now answer this myself. Our app has gone through the review without any issues. Our Restful web service will only serve traffic over IPv4 and nothing has been flagged by the review team.
I now believe that the requirement is simply that the app supports IPv6 (which in our case it does). So in the future when we completely run out of IPv4 addresses and have to use IPv6, our app will function properly without any need for an update.
Also, I've read somewhere that the ISPs can route the IPv4 traffic over IPv6 network so this scenario would also be covered because our app supports IPv6.