Sometimes, when I unlock my phone and immediately turn it into landscape mode, Siri activates. I've had this occur on different phones (4, 4S and 5) and in different versions of iOS, all the way back since Siri was first introduced. I guess it's not big deal, but it has always bothered me on some level. I don't want Siri to activate, I just want to go into landscape mode. Is this supposed to be normal or is it a glitch that Apple hasn't ironed out? If it's a feature, is there a way to prevent this from happening?