I've just tried the board now. Compiling one of the provided Adafruit sketches yields the following error message. Ignore the Galileo bit, I'm using an Edison
Arduino: 1.5.3-Intel.1.0.4 (Windows 7), Board: "Intel® Edison"
In file included from C:\Arduino_Galileo\hardware\arduino\edison\cores\arduino/Print.h:26:0,
from C:\Arduino_Galileo\hardware\arduino\edison\cores\arduino/Stream.h:26,
from C:\Arduino_Galileo\hardware\arduino\edison\cores\arduino/HardwareSerial.h:24,
from C:\Arduino_Galileo\hardware\arduino\edison\cores\arduino/TTYUART.h:5,
from C:\Arduino_Galileo\hardware\arduino\edison\variants\edison_fab_c/variant.h:20,
from C:\Arduino_Galileo\hardware\arduino\edison\cores\arduino/Arduino.h:33,
from C:\Workspace\Galileo\libraries\Adafruit_NFCShield_I2C\Adafruit_NFCShield_I2C.cpp:44:
C:\Workspace\Galileo\libraries\Adafruit_NFCShield_I2C\Adafruit_NFCShield_I2C.cpp: In static member function 'static void Adafruit_NFCShield_I2C::PrintHex(const byte*, uint32_t)':
C:\Arduino_Galileo\hardware\arduino\edison\cores\arduino/WString.h:37:93: error: 'PSTR' was not declared in this scope
#define F(string_literal) (reinterpret_cast<const __FlashStringHelper *>(PSTR(string_literal)))
^
C:\Workspace\Galileo\libraries\Adafruit_NFCShield_I2C\Adafruit_NFCShield_I2C.cpp:142:18: note: in expansion of macro 'F'
Serial.print(F("0x"));
^
C:\Workspace\Galileo\libraries\Adafruit_NFCShield_I2C\Adafruit_NFCShield_I2C.cpp: In static member function 'static void Adafruit_NFCShield_I2C::PrintHexChar(const byte*, uint32_t)':
C:\Arduino_Galileo\hardware\arduino\edison\cores\arduino/WString.h:37:93: error: 'PSTR' was not declared in this scope
#define F(string_literal) (reinterpret_cast<const __FlashStringHelper *>(PSTR(string_literal)))
^
C:\Workspace\Galileo\libraries\Adafruit_NFCShield_I2C\Adafruit_NFCShield_I2C.cpp:173:20: note: in expansion of macro 'F'
Serial.print(F("0"));
^
C:\Arduino_Galileo\hardware\arduino\edison\cores\arduino/WString.h:37:93: error: 'PSTR' was not declared in this scope
#define F(string_literal) (reinterpret_cast<const __FlashStringHelper *>(PSTR(string_literal)))
^
C:\Workspace\Galileo\libraries\Adafruit_NFCShield_I2C\Adafruit_NFCShield_I2C.cpp:177:20: note: in expansion of macro 'F'
Serial.print(F(" "));
^
C:\Arduino_Galileo\hardware\arduino\edison\cores\arduino/WString.h:37:93: error: 'PSTR' was not declared in this scope
#define F(string_literal) (reinterpret_cast<const __FlashStringHelper *>(PSTR(string_literal)))
^
C:\Workspace\Galileo\libraries\Adafruit_NFCShield_I2C\Adafruit_NFCShield_I2C.cpp:180:16: note: in expansion of macro 'F'
Serial.print(F(" "));
^
C:\Workspace\Galileo\libraries\Adafruit_NFCShield_I2C\Adafruit_NFCShield_I2C.cpp: In member function 'boolean Adafruit_NFCShield_I2C::inDataExchange(uint8_t*, uint8_t, uint8_t*, uint8_t*)':
C:\Arduino_Galileo\hardware\arduino\edison\cores\arduino/WString.h:37:93: error: 'PSTR' was not declared in this scope
#define F(string_literal) (reinterpret_cast<const __FlashStringHelper *>(PSTR(string_literal)))
^
C:\Workspace\Galileo\libraries\Adafruit_NFCShield_I2C\Adafruit_NFCShield_I2C.cpp:1147:20: note: in expansion of macro 'F'
Serial.print(F("Don't know how to handle this command: "));
^
C:\Arduino_Galileo\hardware\arduino\edison\cores\arduino/WString.h:37:93: error: 'PSTR' was not declared in this scope
#define F(string_literal) (reinterpret_cast<const __FlashStringHelper *>(PSTR(string_literal)))
^
C:\Workspace\Galileo\libraries\Adafruit_NFCShield_I2C\Adafruit_NFCShield_I2C.cpp:1153:20: note: in expansion of macro 'F'
Serial.println(F("Preamble missing"));
^
C:\Workspace\Galileo\libraries\Adafruit_NFCShield_I2C\Adafruit_NFCShield_I2C.cpp: In member function 'boolean Adafruit_NFCShield_I2C::inListPassiveTarget()':
C:\Arduino_Galileo\hardware\arduino\edison\cores\arduino/WString.h:37:93: error: 'PSTR' was not declared in this scope
#define F(string_literal) (reinterpret_cast<const __FlashStringHelper *>(PSTR(string_literal)))
^
C:\Workspace\Galileo\libraries\Adafruit_NFCShield_I2C\Adafruit_NFCShield_I2C.cpp:1201:24: note: in expansion of macro 'F'
Serial.println(F("Number of tags inlisted:"));
^
C:\Arduino_Galileo\hardware\arduino\edison\cores\arduino/WString.h:37:93: error: 'PSTR' was not declared in this scope
#define F(string_literal) (reinterpret_cast<const __FlashStringHelper *>(PSTR(string_literal)))
^
C:\Workspace\Galileo\libraries\Adafruit_NFCShield_I2C\Adafruit_NFCShield_I2C.cpp:1207:20: note: in expansion of macro 'F'
Serial.print(F("Tag number: "));
^