I hate my car's chunky remote control and I wish to use the NFCRing as a substitution.
My idea is

1. instal 2 NFC detectors(1 for lock, 1 for unlock) on car, powered by car battery.
2. connect detectors to a remote control to send signals or even connect to a mini step
   motor to physically press the remote button.
3. get a NFCRing, or NFC tag, done.

However, anyone has any idea on the programable "NFC detector"? I'm thinking smartphone
but a smartphone-like device is too big for this problem, or is it the only choice?

Thanks for your help.