DIOTSR Men's 2 in 1 Running Training Shorts Gym Workout 7" Athletic Shorts with Towel Loop

How does the sizing work?

Is the phone hidden pocket on the left leg?

How secure is your phone in the hidden pocket when you run (i have a iphone x)?

Is the liner supposed to be tight? got a m because i’m a 30 in waist. liner is snug, but does not feel “tight.” should i get a s?