The notification body contains full information - current values of all primary cycles along with their interpretation, plus your current age in days, as well as in years months and days. In the notification, you can tap on the "Open" action button to launch the UI part which additionally shows the monthly graph. In the app you can also change the birthdate and notification time, or you can tap on the "Get Now" button to have the biorhythm notification sent to the Hub instantly. There is no need to delete the notifications - each day the existing one gets automatically replaced by a new one so that always only the current Biorhythm data is shown.
There is also a "Share" feature to quickly and easily share current Biorhythm values via SMS, email, social services, etc.
The headless part is very small and written entirely in C++, it uses virtually no CPU time or power (0.05% or so) so it can be kept running all the time without any impact on phone's performance or battery life.
Just configure your birth date and notification time, close the app and forget about it - since then you'll be getting your daily Biorhythm readings automatically in your Hub, at the chosen hour.
Why another Biorhythm app? Because in 2002 I wrote for the Nokia Communicator probably the first Biorhythm app ever made for smartphones. So this is simply a continuation / evolution of the oldest Biorhythm app for smartphones.
Full Touch phones:
Phones with square screens (Passport, Q10, Classic, etc.):
Headless Biorhythm is available for all BlackBerry 10 smartphones: