Firstly thanks for a great product, I'm having bucket loads of fun with NFC tags.
After some research I found that the possibility for NFC p2p capability is still under development, for example p2p between the shield and an Android NFC-enabled smartphone communicating via the initiator-target-protocol.
The other method for an NFC shield to "communicate" with an Android smartphone requires the Smartphone to emulate a Passive NFC tag (ensuring a static UID), but this is impossible due to limited releases of Google API's.
What I'd like to know is how can the shield detect the proximity of another NFC antenna/reader (ie. in a smartphone), not necessarily establish a p2p comm with it nor try to identify the UID or RID, but just detect that it is present?
Looking forward for your reply!