Apple Insider just reviewed the BACtrack Mobile Smartphone Breathalyzer, giving it high ratings for performance, features, and accuracy. They also made special mention of the BACtrack app's integration with Apple Health.
"The BACtrack Mobile is a tiny handheld accessory that can provide users with their blood alcohol content. While it's been around for a few years with both iOS and Android compatibility, the device's accompanying application was recently updated to support the HealthKit tools introduced in iOS 8."
The reviewer was impressed by the Bluetooth capability, battery life, ZeroLine technology and feature set. They also made mention of the accuracy and utility of the breathalyzer.
There were only 2 drawbacks mentioned--the security concerns of the cloud storage of data, and the lack of a display screen on the unit itself--however both items were but a "minor blemish for what is otherwise an excellent product."
Conclusion: 4.5 / 5 stars.