Originally Posted by LostFool:
“It's just a standard micro-USB charger. If you don't have one from another device you can get one for pennies on Ebay.”
The original HTC charger is capable of providing the full 1A of current - and so the phone charges faster.
Some chargers, especially cheaper ones, don't do this. The phone charges much more slowly.
I've had chargers that claim to provide 1A of current, but obviously don't do whatever it is that triggers the phone into drawing that much current.