I created a test app for scanning NFC tags. As far as I know, it's working like it should, the Scan dialog comes up, but when I try to scan an NTAG 203 tag, it doesn't even do anything, not even give me an error. I also downloaded the following app and got the same results. It doesn't acknowledge the NFC tag at all.
I'm testing on an iPhone 7 with iOS 11
https://itunes.apple.com/us/app/nfc-reader/id1286968328?mt=8