Thank you, i think to use libnfc and rfidiot libreries to read tags... I thought initially use only ultralight tags to simplify the project , after I will try to improve it .
Now I will try to study the nfc protocol and these libraries ...

thanks to all for the advice !

Thank you all,
I do not have much experience in this field.

I'm using NFC UART pn532 connected to raspberry.
I want to write using an application andorid any textual tag and I want to see the text written on raspberry with library commands libnfc.

thank you, I have communication problems . I can not read by the reader NFC PN523 (connected to raspberry) data from a tag through the library libnfc. Have you a solution?

Hi nancy, I have the same problem, you have found a solution?