Fitcat Body Scale app helps you to track you body weight for fitness (none medical usages) tracking only.

All additional analytical values have not been validated by the FDA or other healthcare institutions and are not intended to diagnose, treat, cure, or prevent any disease or health condition.

Apple HeathKit is integrated in this app for users who wish to sync data to Apple Healthkit.

Note:
Below are the scientific explanation on how the app analyzes data from the body fat scale:
BMI: https://www.nhlbi.nih.gov/health/educational/lose_wt/BMI/bmicalc.htm

BFR:
https://www.healthline.com/health/exercise-fitness/ideal-body-fat-percentage

BM:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4716172/

ROM:
https://journals.sagepub.com/doi/pdf/10.1177/0379572117697534