If I'm planning to implement NFC payment functionality using a webview in an app, are there any specific Apple policies I should be aware of? The official website doesn't seem to have detailed guidelines, Any guidance or references would be helpful.
Unfortunately this is a very open ended question which is difficult to answer here without understanding what it is you are trying to accomplish. There are many factors and policy differences based on what you are implementing, for what purpose, and in what locations.
In any case, to implement NFC payment functionalities, you will need specific entitlements from Apple. When applying for them, you will be able to explain in detail your product plan and any details, and if you are approved, at that point any policies with regards to your implementation will become clear.
