Here is a smart bracelet that helps you get in touch with your contacts when in trouble. The CARRAT Bracelet is available in 18K gold and 925 silver versions. It combines with your phone for accurate GPS tracking and emergency phone calling. You can use the companion app to set up contacts and configure automatic emergency messages.
You simply have to push the bracelet twice to activate a call to your main contact and send your location via text to others. The battery lasts up to 12 months. You can find this project on Kickstarter.