Hi, the blood pressure function is really useful. As someone who has to take regular readings, I know all about white coat syndrome!! As soon as the cuff is put on it can flip a psychological switch that skews the reading. For some reason, being able to casually flick the watch blood pressure reading app on doesn't have the same effect.
The calibration thing can be a lite annoying, but this is the best way to ensure the readings remain accurate.
The other useful thing with the app is that your readings are recorded so it's a handy reference for the doc.