Strong.app - Strenght training logger.
wger - FLOSS workout, fitness and weight manager/tracker written with Django
Strongify - Strongify is the easiest workout tracker app. Enter the number of reps and the weight you lifted in just a few taps. Create any exercise that you want and track your progress over time.
Burn.Fit - Burn.Fit is #1 Fitness log journal app that helps fitness lovers to track their workout to maximize results. Start track your fitness and home workout routines with Bunn.Fit
Hevy - Simple workout logging, insightful analytics, and a growing community of gym athletes.
Liftosaur - Free weightlifting tracking app where you can code