Compare software

Lens HRVHRV4Training
Free

Free and open source under the GPL-3.0 licence.

 Paid

Paid app, with additional Pro and Teams options for coaches.

Android Android, iOS
  • Uses only the phone camera, no extra sensors
  • Open source and available on F-Droid
  • Measures HRV with the phone camera, no sensor needed
  • Supports Bluetooth chest straps, Apple Watch and Oura
  • Camera PPG is less precise than a chest strap
  • Android only
  • Needs consistent daily measurements to be useful
  • Pricing not detailed on the homepage
Downloadable app Downloadable app
Open source Closed source
License: GPL-3.0 License not stated
Not stated if an account is needed Not stated if an account is needed
Not stated if it works offline Not stated if it works offline

Checked October 2, 2026

Checked September 24, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.