If you want to charge your mobile faster put it on airplane mode
Or turn it off.
Probably best to turn it off completely. The battery doesn't seem to get as hot either.
Use a shorter USB cable with the least resistance
It depends on the phone as well as the juice (amps) you're charging it with, as to whether it'll make any difference if you're charging whilst it's on or off. I plug my phone and my camera into my powered USB hub. If you use your computer's USB port directly for charging, use a USB 3.0 port if you have both USB 2.0 & 3.0 ports. USB 3.0 supplies 1 amp whereas the older USB 2.0 is just half an amp.
@masterluke Thank you but that is all foreign to me lol