So far I have charged mine a few times. It seems like it is pretty darn slow.
But a MAJOR precaution. You MUST use the cable that came with your S3 to charge it. If not, you might be waiting for a loooong time. Also, I would use the wall adapter that comes with the phone.
I tried using a variety of cables I had used in the past to charge my DX and all of them resulted in extremely slow charging.
Also, using the S3's cable with my old motorola wall adapter resulted in slower charging (not suprising since it has lower output)
I am curious if the new pin arrangement in the usb port that makes the S3 require a different MHL adapter is to blame for my old cables not working as well to charge the phone. If anyone knows I would love to hear.
I use an old LG charger at home (1000 mA output) and a old generic verizon wireless charger in office (800 mA output). I use my old Droid 1 usb to connect to my computer for transfer.
It definitely depends on the output of the charger. direct corded wall chargers usually have higher output, likewise direct corded car chargers. USB chargers that plug in to adapters for car and wall usually are a little lower (my Motorola 2 port usb car charger does 700 mA, and my old motorola usb wall adapter from my droid is 850 mA), and plugging into PC is the lowest (100 mA to 500 mA on usb 2.0). http://en.wikipedia.org/wiki/Universal_Serial_Bus
do the math: if your usb is only giving out 100 mA per hour (guessing the phone is actually on and using some of the max to power the device) to charger your phone which has a 2100 mA capacity battery.
My old car usb adapter i got only had output of only 400 mA and using my doid 1 with navigation on, it would not keep up and the phone would actually drain while plugged in while running nav.
I've been using a variety of wall chargers, both corded and USB. I'm not sure of the output on any of these, but they all seem to charge.
I'm interested when you mention the car charger output. When I use navigation for any length of time (we've gone on two trips this summer: one 3 hours, one 4 hours), the charger keeps the charge somewhat stable, but doesn't give any additional charge. Maybe we need to look into stronger car chargers?
I went in and exchanged my original s3 today @ the vzw store -- here's hoping the new one charges normally.
Beka -- I'm interested, when you have yours plugged in to the charger and you're actually using the device, will it charge, stay neutral, or lose charge slowly?