I have a BT connected HR monitor (decathlon HRM band) that I want to use for tracking my HR during treadmill running and crossfit. However, since I want it all offline without connecting to an account in the cloud somewhere, this seems to be near impossible. I can easily get HR readings from the device via BT, but I haven't found an app that allows me to do the above mentioned tracking where the HR data is logged with exercise duration.

I use the HRM band with opentracks for outside running, and it works great within opentracks (aside from horrible data visualization). But opentracks doesn't export any HR metrics unfortunately. And opentracks is really terrible for recording workouts that don't use GPS, e.g. it won't allow me to easily edit speed and distance for treadmill runs and has tons of useless fields for crossfit workouts.

Anyone know of an app that allows for offline generic HR logging with a BT HRM? Bonus if it can record for different activities, but I will settle for generic workout category.