**5.3 Reader/writer mode**

In reader/writer mode, the device must be able to read and write with different types of NFC tags. This mode enables one NFC mobile to exchange data with one NFC tag. In reader/writer mode, most NFC devices act as readers and works in active mode to read the content of tag, such as contactless smart cards and RFID tags. In order to interact with tag appropriately, the device needs to detect the correct tag type. For that, the NFC device relies on an anticollision algorithm to select one tag when device comes across two tags simultaneously. An NFC device also works in writer mode, it can write data to the tags having writer application, such as TagWriter [55, 56]. In reader/writer mode, the NFC devices are compliant with ISO/IEC 14443A/B or Felica schemes tag types [14]. Some of the applications of reader/writer mode are smart posters, remote shopping, remote marketing, and so on [18].
