For most athletes, that’s as high-tech as safety notifications get — a Post-it on the fridge. And if you’re not back by 12:30, expect someone to come looking for you.
We all worry about safety from time to time, and our family and friends worry even more. So Strava made a feature to take some of that concern away and gives our loved ones peace of mind.

Beacon, the newest Premium feature, is the note on the fridge for the connected athlete. Instead of a lonely sticky note, Beacon safety contacts will get to see where you are during an activity in real time on a map.
If you aren’t back on time, they can check to see where you are or if you’re stopped. If something were to happen to you, they’d be able to see your GPS location.

More on: http://blog.strava.com/turning-on-the-beacon-12207/