I consider stretching to be separate from mobility work. Mobility work includes stretching but goes beyond it, at least that is my experience. I have to do quite a lot of mobility work after a lifetime of being too sedentary. Much of it includes some pretty extensive exercises, some of which includes the use of dumbbells, kettlebells, and dowel rods to help me target the appropriate areas. This aggressive approach is paying off in ways that less, intense, methods were not. Stretching is very important, though the question of doing it before or after exercise will have a different answer depending on who you ask. Personally I won't do anything without at least some light stretching and foam rolling prior, and depending on the workout I may do extensive stretching afterwards.
I stretch in between sets of weightlifting and also do weighted stretching in some of the movements like bench flies, stiff-legged deadlifts, good morning etc. I pulled a hamstring a few weeks ago so be careful if doing weighted stretching, but it is very effective, and my mobility and strength are now better than ever…
Here are my favorite stretches, they're specifically for improving your mobility to squat and perform the olympic lifts but they're still my favorite all around lifts.
Stretches and Mobility Drills to Prepare for the Snatch and Overhead Squat | FITNESS PAIN FREE
Contains all video demonstrations. I'd do these stretches after exercising or before squatting or olympic lifting if you do those exercises.
Hope that helps,
Dan Fitness Pain Free
Thanks for all the answers. Certainly learned some new things about stretching and mobility.