This suggestion is mostly directed to blokes who like to carry their wallet in their back pocket. The problem is that when they then sit on it, even in the car, it actually tilts your pelvis out of balance.
This puts added strain into the sacroiliac joints, the lumbar spine and additional pressure into the piriformis muscle that can create sciatic type symptoms. The same message can now be applied to a new generation of guys and gals who carry their phone in the same position.
Take it out!