Apple iPhone Charging via USB hub
Charging through a hub slows down the process by up to 50 percent -- especially if the hub lacks its own AC power connection.
9 Ways to Charge Your Smartphone Battery Faster
Plugging into your computer may be the slowest way to charge your smartphone battery.
When your smartphone battery power runs low, it's time to plug it into your laptop for a recharge, right? Not so fast ... literally. Pulling power from your laptop's battery or through the machine's power cord will charge up your smartphone, camera, music player or USB-connected small device, but it will take a while.