NFC is a set of short-range wireless technologies, typically requiring a distance of 4 cm or less.
NFC operates at 13.56 MHz on ISO/IEC 18000-3 air interface and at rates ranging from 106 kbit/s to 424 kbit/s.
NFC always involves an initiator and a target; the initiator actively generates an RF field that can power a passive target.
NFC peer-to-peer communication is possible, provided both devices are powered.
There is no link level encryption built into NFC
On Android
NFC allows you to share small payloads of data between an NFC tag and an Android-powered device, or between two Android-powered devices.
Android framework APIs are based around a NFC Forum standard called **NDEF** (NFC Data Exchange Format).
On Android NFC is off when the screen is off (no butt sniffing)
No API support for card emulation
Supported Tag Technology
It is mandatory for all Android NFC devices to support the following tags:
Class
Description
NfcA
Provides access to NFC-A (ISO 14443-3A) properties and I/O operations.
NfcB
Provides access to NFC-B (ISO 14443-3B) properties and I/O operations.
NfcF
Provides access to NFC-F (JIS 6319-4) properties and I/O operations.
NfcV
Provides access to NFC-V (ISO 15693) properties and I/O operations.
IsoDep
Provides access to ISO-DEP (ISO 14443-4) properties and I/O operations.
Ndef
Provides access to NDEF data and operations on NFC tags that have been formatted as NDEF. Support NFC Forum Type 1, Type 2, Type 3 or Type 4 compliant tags
The following tag technologies are optionally supported:
Class
Description
MifareClassicProvides
access to MIFARE Classic properties and I/O operations, if this Android device supports MIFARE.
MifareUltralight
Provides access to MIFARE Ultralight properties and I/O operations, if this Android device supports MIFARE.
