If you sit all day staring at a screen, do yourself a favor. Don't follow that up with a commute home spent staring at an even smaller screen.
Sometimes it feels as if all of our advances in technology are leading us on a backward evolutionary slide. We came out of the womb small, but gained the strength to be tall. Unfortunately, our gadgets have done a great job pulling us back into that fetal position. Don't let them.
If you find that your neck and shoulders are sore and painful, don't hit the panic button right away. Rather, try the simple practice of putting your phone away, getting the crown of your head as tall as possible, and letting your shoulders sit back in a relaxed position. You may find that a simple postural "re-set" is all you need to alleviate your discomfort. If that is the case, then try to work in more resets throughout your day until you restore the naturally good posture that you likely once possessed.
Good posture can help minimize unnecessary and annoying aches and pains. It starts with awareness. Try giving your electronics a rest, get your head up, and see what else is going on. Your neck and shoulders will thank you.