Does Viiiiva work with HRV applications? October 02, 2019 17:06 Updated Yes, Viiiiva measures R-R intervals with 1ms accuracy and is, therefore, suitable to use with your favourite HRV apps. Related articles With which apps can I use Viiiiva? Is Viiiiva waterproof? How do I know which Viiiiva is mine when I'm in a group? Can I use Viiiiva with my fitness equipment? How Do I Bridge ANT+ Sensors to My Bluetooth Device Using Viiiiva?