Here is a smart Bluetooth gadget that shows your BAC, so you can make smarter decisions. The WearSmith has an OLED display and a portable design. Just blow into it for a couple of seconds to start seeing your results. The companion app analyzes how long it will take you to recover. You can use the device without the app though.
WearSmith is compatible with iOS and Android devices. It weighs only 19g. Expected to ship in September.