Love it

Im a numbers guy and this app has numbers out the wazoo. The science behind it is, in my opinion, well supported and the outputs from the app correlate well with more traditional HRV monitors (I use a FR910 and Firstbeat). Definitely worth the $$ if you like to use numbers to improve training efficiency. No stability issues for me.

Awesome by design about HRV4Training, v4.8.0