Keeping records is a great way to stay on track and provides motivation for future workouts. I have been recording my workouts for over 30 years in notebooks. Of course in this day and age there should be an app to replace all that paper I have accumulated.
Gym Genius is quite flexible and adaptable, and you can look back at recent workouts fairly easily. I do like having the workout graphs and the body statistics are a great way to keep track of yourself.
Personal-record tracking is a neat feature, but I wish it could be expanded. It is nice to see the highest weight you have ever moved, but the # of reps play an important part as well. For example, you may have benched 375 for four reps, but it would be helpful to easily find how many reps you did with 350, for the days you are going a little lighter.
When building a custom workout, many different lifts are already listed, organized by body part, so you can find much of what you need quickly. And, for the more advanced gym rat, you can also create your own entries for any unusual stuff you may do when throwing around iron. Do plan, however, on spending some time away from the gym when building a custom workout as it does take some time to customize everything.
This app covers what I need for tracking weightlifting quite well. The only negative comment I have is that for a time-sensitive lifestyle, this app is a bit cumbersome to use... building a workout on the fly does take some time. On heavy days with longer rest periods this is not so bad, but on medium days with a faster tempo, especially when spotting a partner, I find it easier to keep using my notebook and put in the entries when I get home. I will say though if you create predetermined workouts and stick to that plan, strictly, using the app in real time is not bad.
Compared to other weightlifting apps I have seen/tried...this is the only one I would recommend.