Name: Barometer
Rating: 3.3 (23 reviews)
Author: AlanSmithee

Simple old-fashioned barometer that displays base level (sea-level) pressure as measured by the watch sensor. Supports millibars (mbar), inches of mercury (inHg), and millimeters of mercury (mmHg) as pressure unit. Pressure unit can be changed from widget settings in Garmin Connect app.

At least in my own testing the watch sensor in Vivoactive HR seems to be pretty accurate. The reading can be easily verified e.g. against airport routine meteorological reports (METARs) that are available for most airports. However, note that Garmin documentation says that accurate reading requires that a GPS altitude has been obtained, in order to take the local (ambient) pressure and convert the barometric pressure to base level pressure.

If you're interested, here are some ideas on how to interpret barometer readings to predict weather: http://www.artofmanliness.com/2015/07/07/fair-or-foul-how-to-use-a-barometer/

Thanks for all review comments and development suggestions. However, I just did this on my summer vacation to amuse myself, so not sure when I will have more time to develop it further. I'm happy to give the source code to anyone who wants to continue development. Just contact me using the "Contact Developer" button above and send me your email address so I can reply.