|Oxygem. Credit: Yankodesign|
Hussain Almossawi's Oxygem is a wearable health tracking ring that will detect low blood oxygen level caused by red blood cells got stuck together. The ring has built-in sensors to monitor oxygen saturation. The ring changes its color after it detects sickle-cell crisis, and sends alters to the wearer as well as notification to the smartphone and nearby emergency service.
Oxygem can be worn like a normal ring and makes it indistinguishable from a traditional ring. (via)