ESP8266 ESP12 wifi module.  This module is very inexpensive (US $3.45 in small quantities) and has FCC certification markings on RF shield.

Wifi has the potential for much higher data speeds than bluetooth.  Documentation for this module is very scarce.  I do not know how difficult it would be to implement into the design.  There does seem to be a large group of enthusiasts that are playing with it and posting about it.

On the Arduino forum there appears to be helpful information about using and programming this module.

www.esp8266.com appears to be a community created and supported forum and wiki dedicated to this family of wifi modules.

This module already has a large open support community which would be valuable for this project.