Tired of doing the old press-and-hold to activate your favorite virtual assistant? We'll forgive you if you've never ventured into the bowels of your iPhone's settings and poked around with Siri's various options, but there's a quicker, easier way to get her up and running and it doesn't require you to press a button.
Head into Settings -> General -> Siri and activate the "Raise to Speak" option.
Once enabled, Siri will start up whenever you place your phone up to your ear -- assuming you're not answering or placing a call, of course. If you are a regular Siri user, you'll find that this option is actually a second or two quicker than the default method.
Warning: Using this feature kind of kills your ability to take fake phone calls in stressful public settings. Putting your phone up to your ear will now produce the signature Siri chime, and your awkward cover will be blown.