Since I posted my article on Disney’s new FuelRod program, other people have also weighed in with their opinions. (Josh from easyWDW seems to make many of the same points I made, so I—obviously—think he did the best job.)
All that said, however, one thing that you should be doing at Disney World, regardless of what battery pack you use (or don’t), is using Low Power Mode on your iPhone while in the parks. (Android apparently has its own Battery Saver Mode, which might have a similar impact, but, I’ve never used Android, so I can’t confirm.)
Basically, when you’re walking around Disney World, your phone is constantly trying to deal with things that suck battery (low or non-existent network connection, you checking the time or trying to refresh FastPass+ availability, etc…). Low Power Mode helps address some of this drain by doing things like reducing background app refreshes and some of the visual effects on your phone. Though I haven’t done extensive comparisons of when my phone dies while in a given Disney Park, I can report that my phone lasts significantly longer when on Low Power Mode. In fact, I’ve even managed a near full Disney day (rope drop at the Magic Kingdom, lunch at Beaches & Cream, visit to Disney Springs, then back to Magic Kingdom for Celebrate the Magic and Wishes) without running out of battery. (Obviously, your results may vary—and I wouldn’t recommend this being your standard operating procedure—but, it’s possible.)
Should you decide to give Low Power Mode a try, turning it on is pretty simple. First, go to the settings app on your iPhone. From there, select the “Battery” option from the third grouping of choices.
On the Battery menu, you then simply turn on Low Power Mode. That’s it.
iOS is kind of aggressive about turing “off” Low Power Mode, so if you happen to plug your phone in (to a charger or battery pack), you might want to check to make sure Low Power mode remained on. (I like to turn Low Power Mode on before I unplug my phone from a charger. That seems to help the automatic shut-offs a bit.)
Hopefully, this tip helps your battery survive a little longer while visiting Disney World. Good luck!