Once upon a time, screen protectors were an absolute must for phones, as the screens were about as sturdy as ice butter. These days? Not really.
Full Disclosure: I was religious about putting a screen protector on my phone. It came to the point that I would buy the protector before buying the phone, so that as soon as the sticker film came out of the screen, I could bring up the protector.
Today, however? I have not had a protector on my screen for two years. Window technology has evolved so much that there is little chance that the screen protector you buy is harder, more durable or has anti-fingerprints technology. Digital superior to that of the ultra-resistant Gorilla glass display of your phone, coated with anti fingerprint and anti-glare coatings.
If your phone spends 90% of your day safely in your pocket, what exactly do you protect it from?
There are, of course, exceptions to the rule. Although my iPhone runs all day in the pocket of my pants, away from anything that could harm him. My wife's iPhone spends all day in her purse, which looks more like a wood chipper filled with makeup clips and keys than a soft and secure pouch that is my pocket. In this case, we are willing to use screen protectors to make ritual sacrifices to protect the screen of his phone.
For more information on why you can probably give up your screen protector (and when viewing one is a good idea), Discover our complete treatment of the subject at Review Geek.