Instead of having to put in each weight and amount of reps for each exercise while working out and having to scroll through the whole lot, perhaps have a drop down for each exercise where if they completed the same weight and reps for all 3 sets it gets added automatically. Have a drop down button for if one set was different e.g for 2/3 sets they did 10 reps at 10kg but the third set they did 8 reps at 10kg.