The free GPS Hiker Tracker Service automatically sends details of hikers' locations to the service provider, the Communications Association of Hong Kong, via mobile or Wi-fi networks. In cases of emergency, family or friends can report a missing hiker to the police and the association will e-mail the location data.
[iTunes] https://itunes.apple.com/hk/app/enjoy-hiking/id405460254?mt=8
[Google play] https://play.google.com/store/apps/details?id=com.hkgeopark.enjoyhiking
