Getting online isn’t hard. Wi-Fi is now considered an essential amenity, like running water. Universal will have free access—including in the theme parks, although the signal may die when you're indoors. 

Your movile phone should work in Orlando; it may not work if you drive far from commercial areas, such as in some remote vacation home developments (although in those cases you’ll probably have Wi-Fi for Internet calling). To buy a pay-as-you-go SIM card, ask for a “no-contract” SIM card.

The theme parks’ new reliance on managing your day via apps drains devices quickly. To have enough juice for a 13-hour day, carry a portable charger or battery. The theme parks have vending machines by FuelRod ( selling $30 pre-filled booster batteries, adapter included; find them in the photo stores by the front gate and sprinkled around the park (ask a cast member where). 

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.