Strong.app - Strenght training logger.
wger - FLOSS workout, fitness and weight manager/tracker written with Django
Liftosaur - Free weightlifting tracking app where you can code
The Fit Tutor - The Fit Tutor is a membership community dedicated to efficient and effective workouts for all...
Bolt - Workout Tracker - Track your progress in the gym and discover new workouts with the most intuitive workout tracker for weight lifting on the App Store.
LiftWeb - Lift is a secure web framework available.