Most Healthkit apps are single-mindedly practical, created with the sole aim of making you healthier or tracking your sleep. This app is the opposite. This app wants to creep you out big time.
Deadline is an iOS app that uses a short quiz and the new Healthkit functionality in iOS 8 to create a timer that counts down towards your death. Although it's just a generic algorithm that forecasts your death, there's still something undeniably creepy about having a clock in your widget screen, just below the weather forecast, cheerily informing me that I've got 54 years, 2 months, 20 days and 22 hours left to live.
I suppose, in some twisted way, it might provide some good incentive to live a slightly healthier life: since the timer uses Healthkit data, which is constantly monitoring how active you are (and things like your blood pressure, if you have the right add-on gadgets), you can make that timer go backwards if you climb enough stairs. [iOS, 69p]