Share GPS can be used to provide GPS from a mobile phone to Linux PC running GPSD. This can be done via Bluetooth connection. The Linux PC can be setup to listen for bluetooth connections on a specific channel. Then Share GPS can connect and provide NMEA position information at anytime.
This is great for headless setups. For example, for a car stereo system using a Raspberry Pi with a Bluetooth dongle, Share GPS can provide GPS for Navigation and Position viewing, without the need for an external GPS receiver setup.
See this guide on how to do it: NMEA Bluetooth for Linux