I'm generally of the impression that any phone with an unremovable battery is never truly "off" at any given time, unless the battery is totally damaged.
PS: I like phones whose batteries are removable, currently use a Nokia Android with a removable one. One advantage is that when the phone drops down, it disintegrates, frame from battery, decreasing the overall impact on the phone.
I remember using a low-energy bluetooth scanner and noticing a strange mac that shouldn't have been present. I really wanted to know wtf was broadcasting it. I searched and searched looking in stupid places. Eventually I settled down and began thinking clearly and looked at my speaker. Yeah, it was as off as the power button could make it, though still on. A good toss across the multi-acre yard and the signal faded accordingly.
PS: I like phones whose batteries are removable, currently use a Nokia Android with a removable one. One advantage is that when the phone drops down, it disintegrates, frame from battery, decreasing the overall impact on the phone.