I own an iPhone 5 and a 12-inch iPad Pro and I ran into this weird problem today where I was unable to reach any Apple related services via my home network. I was suddenly unable to connect to the App Store with both of my devices both via Wi-Fi when everything was just fine yesterday. It wasn't like my Internet's down or anything - I can go to any other sites just fine, and all of my games that need to be online didn't run into any problems, and I don't think anything has changed about my router settings either.
The first thing I checked was if App Store was down - unlikely, but possible - so I switched over to my phone's cellular network, and it connected to the App Store no problem. I was able to reach the store with my iPad through my phones network too.
I decided that my network is just acting weird, and with my iPad I consulted Google for an answer. That led me to, unsurprisingly, the Apple support site, which I was unable to open. So I tried again with my computer, which is connected to the router via Ethernet. That, too, failed, but at least Chrome gave me a better idea of what the problem is, which apparently had to do with apple's DNS address. I did the only thing I knew how, and that is to clear the DNS cache, which sadly did not work either.
At this point, I am both confused and out of ideas. I would like to ask if anyone can give me some insight. What is happening, why is it happening, and is there anything I can do to fix it, or is it something I can just wait out?
