When connecting an ordinary USB cable to a smartphone, it seems to become standard charging, so there was no advantage of high power output. I told that there is a USB cable exclusively for charging, and when I used it, I was able to charge it in a relatively short time. I think that it is good if it is in the item description. It seems that iPod Classic purchased in 2009 is charging, but it did not become fully charged without displaying during charging as well. These are the results of connecting alone. It may be compatible depending on equipment.