My apologies in advance if this topic has already been posted and discussed ad nauseam, and yes, forum regulars, I did search before posting. I am overseas and didn't want to take a chance with getting a big AT&T bill this month. So, I'm leaving my iPhone on Airplane Mode. I noticed that my battery seems to be at half power at the end of the day even if I may have only played music for 2 hours, max. Should I be concerned about this? The hard drive is almost completely full (~15 GB), but that shouldn't be the cause of the battery drain, right? Is this something I should get looked at by the Apple Store when I get back home?