OpenPicus is open source Hardware and Software wireless platoform born to easily enable Smart Sensors and Internet of Things. You can develop your applications on modules using the free IDE.
It's modular. Different types of modules are mechanically
identical and pin to pin compatible to each other.
Based on freeRTOS to manage Protocol Stack and
Application. But you don't need any expertise about OS or Stack!
Web Site: http://www.openpicus.com/cms/