The GeoSkeeper personal tracker and communication system was recently unveiled. The watch-like device has GPS and mobile phone functionality that allows users to send their coordinates if they are calling for help. The device can be programmed remotely, allowing caretakers to set phone numbers into memory and predefine a geographic area, the breach of which will trigger an alarm call.
http://www.aerotel.com/en/products-solutions/lifecare-mobile-solutions/geoskeeper.html