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This RFID tag is really unique: it works with mobile phones just like other RFID tags, but you can reprogram it over I2C. The tag shows up as an ISO/IEC 15693 (13.56MHz) chip which is readable by phones and tablets. This could be interesting in situations where you want a tag that can be re-written dynamically when connected to a controller.
ST has written a handy library that you can easily use to write NFC URLs to the chip over I2C. You can use a M0 or other SAMD chip (or better) to communicate with the ST25DV.
More information is available on the website of Adafruit.