With all the concerns about women being safe whilst out, I’d like to mention HollieGuard, named after Hollie Gizzard who was murdered one night.
Hollieguard is an app for Android and iPhone that uses the features of your phone to help people out and about.
Capabilities in brief include monitoring your progress along a route, sending emergency messages and location to preset numbers, as well as transmitting audio and video.
User reviews vary widely in their opinions but the app developers do respond.
Do have a look