GPS Auto-Responder is an Android app for allowing a trusted person to discover your location. It generates a unique link to find the device from web browser. The app will notify its user each time, when the link is used.
When the link is used, the device is notified and will transmit its GPS coordinates for 60 seconds and then stop. The link may be used multiple times which will cause additional notifications to show on the device.
It uses GCM so it runs only when the location is being displayed to the user.
Code license: GNU GPL v3
Compiled GPS Auto-Responder in Google Play
See also compatible server webapp for Google App Engine - GPS Auto-Responder GAE