Near Field Communication (NFC) is a wireless communication technology that allows the exchange of data between two devices by bringing them within 4 cm of each other. It is also known as RFID (Radio-Frequency Identification).
The compatibility of NFC devices is not so much a problem as it was in the past. There are many manufacturers who are using and improving upon NFC technology, and there are more and more devices that come with the capability of NFC always enabled. This means that the user does not need to manually activate NFC before scanning a tag.
In the below table, an overview of the NFC compatibility of Apple iPhones. As mentioned, iPhones are conservative with respect to NFC implementation and compatibility among Android devices is further ahead.
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