Lots of info in this thread.
WORWIG has the key bit of info for any smartphone that doesn't have a proprietary charging scheme.
The USB Committee charging standard for "dumb" chargers is shorted data pins. A dumb charger is a wall charge or power port such as those being discussed here. This charging scheme has been around awhile and is loosing its utility as phones get smarter and other charging schemes are introduced (more about this later).
The charger that comes with your Android phone will have shorted data pins unless it has a proprietary quick charge scheme.
Dumb chargers are in contrast to smart devices such as laptops and tablets.
At this point it gets complicated. Phones that are designed to adhere to the USB standard check the data lines to see if they are shorted (loop back mode) or have voltage that indicates signals from a smart device. If it sees loopback it goes to full charge rate.
If it sees voltage it throttles back to 500mA or less since the smart device may adhere to the USB 1.0 or 2.0 standard of 500mA max output.
Apple screws all Android users with their non-standard charging requirement. They require a differential voltage on the data pins. They use this scheme to determine if the device is an iPhone or iPad. This prevents a user from damaging an iPhone charger cube by trying to charge an iPad.
Android sees these differential voltages a data and throttle back to less than 500mA regardless of the maximum current available from the charger.
Funny story - Google called me to complain that the USB power ports that we shipped them for their autonomous vehicle testing wouldn't keep their Android tablets charged. They weren't aware they were getting screwed by Apple! We set them up with some of our Red Band cables and it was all good again.
Now to proprietary charging schemes.
Qualcomm is the largest supplier of smartphone chips in the world. EVERYBODY uses them, even Samsung (Samsung also uses their own chip in some phones but none that are exported to USA).
Qualcomm has a kick-ass fast charge scheme called QuickCharge. It will output crazy high current and even goes above the USB 5.0 VDC standard.
Of course if you buy a smartphone with a Qualcomm chip in it, the charger that you get with it has Quick Charge capability. BTW - the current QuickCharge version is QC 3.0. They just introduced QC 4.0 with some really cool features.
There are some other quick charge schemes but I haven't had a chance to test them.
One more charging scheme that will probably become the standard. USB-PD. This is a USB Committee response to proprietary QC schemes and does all of the things that Qualcomm QC does.
Google recently recommended smartphone suppliers use only USB-PD. For more infor do a Google search on:
Google to OEMs: Don’t use Qualcomm Quick Charge; USB-PD is the future
OK, I'm out of breath so I'll shut up.
-Shov
WWW.3BRPOWERSPORTS.COM Putting the POWER in powersports