Image J
Website: https://imagej.nih.gov/ij/
Image J is a free software for measuring distances and areas in 2 dimensional images and for analysing images.
Heart Rate Variability (HRV)
Website: https://www.kubios.com/hrv-standard/
Kubios is free software for heart rate variability analysis. A guide to HRV in horses can be found here> LINK

JASP – Free Statistics Software
Website https://jasp-stats.org/

Real Statistics for Excel
Website: https://real-statistics.com/free-download/