Just a small tip that helps immensely. It may have been said before, but if so, here's a reminder.

Every time you're out and feel a bit uncomfortable in a social situation, or you're between sets and not talking to anyone for a minute you get that temptation to pull out your phone to appear busy... DON'T DO IT.

Instead, try looking around and count the number of people who are on their phones and smile to yourself, because you are already demonstrating higher value than they are. That should boost your confidence enough to re-engage in being social.

Whenever I leave my phone in my pocket, I end up meeting people, and I usually close at least one girl by the end of the night. Your email/internet connection is a crutch, and it holds you back.

As even more incentive, while you're counting who is on their phone, find a girl in that group and go talk to her. If she's on her phone, she's in serious need of someone to relieve her anxiety and will usually be very grateful for an approach. Even if she's just standing with some guy nervously checking his phone, if you walk up and give her that charming, cocky smirk and introduce yourself, you'll seem like a real man to her compared to the guy being anti-social on his phone.

Force yourself to be present and approachable, women will notice.