I disagree.. My LTE iPhone lasts about a day of normal usage (more data than voice calling these days). That's about the same as my Android Galaxy Nexus HSPA phone before that, and my Blackberry 3G phone before that.
Come to think of it I don't think I've had a phone in a very long time (without stretching back to the olden Nokia days) that reliably lasted more than a day without an augmented battery pack.
I'd suggest the size/brightness of a phone screen draws down the power more than an LTE radio.